Mineral Collection Images

My Mineral Collection, Miscellaneous Systematic Oxides Page

These are my oxides. Oxides have the widest range of properties of all the mineral classes.
Oxides on Other Pages
Another bixbyite, chrysoberyl, ruby, and sapphire are on my gemstones page. See my quartz page, though there is a specimen here with "beta quartz". Cuprite, partzite, tenorite, and tenorite var. melaconite are on my copper minerals page. Bindheimite, cesarolite, minium, and plattnerite are on my lead minerals page and see a plattnerite-tipped aurichalcite on my zinc minerals page. For tellurite, see spiroffite on my sulfates page; mackayite is also there. Gahnite and zincite are on my zinc minerals page.
Oxides Info
I've kept the spinels here rather than put them on my gemstones page - the spinel group comprises a lot of mixed oxides. Most of mine are not gemstone or jewelry quality. Hydroxides are also included here. The cassiterites now have their own page. Fergusonite is now considered a true niobate (columbate) - it's now classified with the sulfates in the Nickel-Strunz scheme (on my pages it's with the tungstates). The wolframite group minerals are now classified as mixed-oxide minerals, so they're here.
Specimens on This Page (links take you to either the first or only specimen)
akaganeite, anatase, apuanite, arsenolite, asbolane, aurorite, avicennite baddeleyite, bahianite, behoite, belyankinite, bixbyite (including an odd bixbyite ps. garnet), boehmite, brookite, brownmillerite, brucite (and variety nemalite) chalcophanite, chromite, columbite-tantalite, coronadite, coulsonite, cryptomelane diaspore (and variety mangandiaspore) feitknechtite, ferberite, feroxyhyte, ferrocolumbite, ferronigerite-2N1S, ferrotapiolite, fluornatromicrolite, franconite, franklinite galaxite, gerasimovskite, gibbsite, goethite, groutite hausmannite, hematite (including a rainbow hematite and variety martite), hercynite, hetaerolite, hollandite, hubnerite, hydrohetaerolite, hydropyrochlore ilmenite, ilmenorutile, iwakiite jacobsite, jeppeite kamiokite, koechlinite latrappite, lithiophorite, loparite, lueshite maghemite, magnesiochromite, magnesiocoulsonite, magnesionigerite-6N6S, magnesiopascoite, magnetite (including a rare dodecahedral crystal, and variety titanomagnetite), deepsea manganese nodule, manganite, manganocolumbite, manganostibite, manganotantalite, manjiroite, montroydite, mopungite, mroseite nolanite, nsutite omsite perovskite, pseudobrookite, psilomelane, pyrolusite (and variety polianite) ramsdellite, ranciéite, romanèchite, roméite, rutile senarmontite, sidwillite, simpsonite, spinel, squawcreekite, srebrodolskite, stetefeldtite, stibiconite, stibiotantalite, stibivanite, struverite tegengrenite, todorokite, trevorite, , tripuhyite, tungstite, turgite valentinite, varlamoffite, vernadite, versiliaite wodginite, wolframite zincochromite, zinconigerite-6N6S, zirconolite

74 Rows
Akaganéite A light-brown coating of akaganeite (a ferric oxyhydroxychloride with a hollandite structure) on a micro of the Nantan meteorite, Lihu - Yaochai area, Nandan County, Hechi Prefecture, Guangxi Zhuang Autonomous Region, China. It's also found as a weathering product of pyrrhotite. Most formulas for akaganeite show a slight amount of nickel present but the formula is often shortened to β-FeO(OH). Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen and the image!	Anatase One of the classic specimens of sharply dipyramidal tetragonal anatase (a trimorph of titanium dioxide with rutile and brookite) - this thumbnail comes from Matshorhe (Matskorhae), Hordaland, Norway. The anatase crystals are a beautiful translucent deep blue. Thanks to Dave Hayward at Lucky Strike Minerals for the specimen and the images!	Anatase Sometimes anatase isn't blue as in this micro of red anatase crystals from Ankogel in the Hohe Tauern Mts, Carinthia, Austria. Thanks to Gerhard Kaller's auction on eBay for the specimen and the image!
Row 2
Anatase A classic sharp 3/8" anatase crystal from the Hardangervidda National Park, Hordaland, Norway. Thanks to Steve & Laurie Adams' auction on eBay for the specimen and the images!	Anatase As noted in my red anatase entry above, sometimes anatase isn't sharply dipyramidal either as in this micro blocky crystal from Minas Gerais, Brazil. Thanks to Jeremy Fuller's auction on eBay for the specimen and the images!	Apuanite and Versiliaite A miniature of a black apuanite (a ferrosoferric sulfantimonate) aggregate on a barite matrix with black microtabular versiliaite (another ferrosoferric sulfantimonate), from the type locality for both - the Buca Della Vena Mine, North of Stazzema, Versilia Valley, Apuan Alps, Italy. Thanks to Anthony Jones' auction on eBay for the specimen!
Row 3
Arsenolite A thumbnail of light-orange arsenolite (arsenic trioxide) crystals on matrix from (possibly) the White Caps Mine near Manhattan, Nye County, Nevada. Even though arsenic trioxide is widely used in industry, arsenolite is too rare to be an ore. It forms an incomplete series with senarmontite, its antimony analog, and is dimorphous with claudetite. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen and the image!	Asbolane An excellent miniature of black asbolane (a hydrated manganese nickel oxyhydroxide with trace cobalt and calcium) and red erythrite from the La Encontrada Mine, Molvizar, Granada, Andalusia, Spain. Thanks to Macarena Alvarez Fornos' auction on eBay for the specimen and the images!	Aurorite Two centimeter-sized chunks of aurorite (a hydrated manganese silver calcium oxide) disseminated throughout calcite from the type locality of the Aurora Mine, Treasure Hill, Hamilton, White Pine County, Nevada. Aurorite was originally thought to be an argentian chalcophanite but the relatively high concentration of silver (~7.5 - 9%) and low zinc content (most formulas don't even show it) led to its being named a new mineral in 1967. Thanks to Chris Auer's (Eureka Micromounts) auction on eBay for the specimen and the image!
Row 4
Avicennite A nice micro of light-pinkish-tan avicennite (thallium oxide) and other thallium minerals from Lookout Pass, Tooele County, Utah. As well known as Lookout Pass is for thallium minerals, MinDat doesn't have it on their site. Thallium oxide is under study for use in solar cells. Thanks to Adam Larson's Adam's Minerals auction on eBay for the specimen and the image!	Baddeleyite Baddeleyite is zirconium oxide - this miniature comes from the Jacupiranga Mine, Sao Paulo, Brazil. Ex: Harry Uhl Collection (1936). Thanks to Jennings "Beau" Gordon's (Jendon Minerals) auction on eBay for the specimen!	Bahianite Bahianite's an unusual mineral - it's an aluminum antimony mixed oxide with a hardness of 9! This waterworn thumbnail of colorless bahianite-filled vugs comes from the type locality of Paramirim das Crioulas, Serra das Almas, Bahia State, Brazil. Thanks to Anthony Jones' auction on eBay for the specimen!
Row 5
Behoite An excellent thumbnail of behoite (beryllium hydroxide) clusters (larger image, right) on natrolite from Mont Saint Hilaire, Québec, Canada. This specimen was collected by Jonathan Levinger in the Fall of 2002. Thanks to Jonathan Levinger's auction on eBay for the specimen and the images!	Belyankinite This excellent miniature of rare cream-colored belyankinite (a hydrated titanium zirconium niobium calcium oxide) on a nepheline syenite matrix comes from somewhere on the Kola Peninsula, Murmanskaja Oblast', Russia - it may be type locality material. Belyankinite froms a series with manganbelyankinite, where manganese replaces the zirconium. Thanks to Thomas Bee's auction on eBay for the specimen and the image!	Belyankinite Another excellent miniature of belyankinite on matrix - this one from a location NOT in MinDat; Kedykverpakhk Mountain, Lovozero Massif, Kola Peninsula, Murmanskaja Oblast', Russia. Thanks to Kristen Burgess' auction on eBay for the specimen!
Row 6
Bixbyite A beautiful pair of bixbyite (iron manganese oxide) cubes from the type locality of the Maynard Topaz Mine in the Thomas Range, Juab County, Utah - the larger one is about 6 mm on an edge. There's a few hematite blades scattered about, as well. It forms a series with manganbixbyite, where the manganese predominates. Thanks to Walter Mroch's (The Gem and Mineral Exploration Company) auction for the specimen and the image!	Bixbyite after Garnet Here's an unusual thumbnail - a bixbyite pseudomorph of garnet from the Thomas Range, Juab County, Utah. Thanks to Anthony Jones' auction on eBay for the specimen!	Bixbyite A beautiful cluster of bixbyite cubes on a hematite after garnet matrix with micro topaz from the type locality of the Maynard Topaz Mine, Thomas Range, Juab County, Utah. The closeup (larger image, center) shows odd "crosshairs" on the bixbyite faces. Thanks to Walter Mroch's auction for the specimen and the image!
Row 7
Bixbyite This is a very large (1.5cm crystal) and complex cluster of bixbyites with attendant sherry topazes (larger image, bottom right) from the Solar Wind Claims near Dugway Pass, Thomas Range, Juab County, Utah. The closeup (larger image, bottom left) shows very fine crosshair etchings on the mirror-bright faces. Thanks to Walter Mroch's auction for the specimen!	Boehmite A micromount of tan boehmite (or böhmite, aluminum hydroxyoxide) on white natrolite from the Saga Quarry, Strandåsen, Porsgrunn,Telemark, Norway. It's dimorphic with diaspore. Thanks to Don Smoley's Minerals & Gems' table at the 2003 Carnegie Gem & Mineral Show for the specimen!	Brookite Brookite is a trimorph with rutile and anatase - this thumbnail's from Magnet Cove, Hot Springs County, Arkansas. The brookites from Magnet Cove are very different from that found elsewhere - the crystals are usually pinacoidally-terminated octahedrons with metallic etched/pitted faces. See my Swiss brookite (next panel) for a more typical appearance. Thanks to the Carnegie Natural History Museum Store for the specimen!
Row 8
Brookite A gorgeous miniature of almost gemmy reddish-brown brookite crystals on matrix from Grindelwald, Bern, Switzerland. Thanks to Frank P. Butler for the specimen and the images!	Brownmillerite Tiny black platelets of rare brownmillerite (a calcium iron aluminum oxide) in a limestone matrix comprise this thumbnail from the type locality of the Caspar Quarry near the Bellerberg volcano, Ettringen, Rhineland-Palatinate, Germany. Synthetic brownmillerite (occuring in Portland and other cements) predates the discovery of the mineral by 32 years. Oxides with brownmillerite-type structures are being studied for solid-oxide fuel cell electrodes. It forms a series with srebrodolskite. Thanks to John Landmesser's auction on eBay for the specimen and the image!	Brucite A beautiful thumbnail of blue brucite (magnesium hydroxide) from the unusual locale of Phalaborwa (Palabora), Transvaal, Republic of South Africa. Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen!
Row 9
Brucite, var. Nemalite The fibrous habit of brucite is named nemalite - these 19" fibers are from the September 2001 find at Asbestos, Quebec, Canada. They're also one of the more nasty types of asbestos - the ferrous oxide on the fibers increases the chance of lung cancer. (I'm keeping mine in a sealed plastic bag.) Thanks to Eric Greene's (Treasure Mountain Mining) auction on eBay for the specimen!	Brucite A micromount of brown brucite on matrix from the Wood's Chromite Mine, State Line Area, Pennsylvania. Thanks to Don Smoley's Minerals & Gems' table at the 2003 Carnegie Gem & Mineral Show for the specimen!	Chalcophanite Black chalcophanite (a hydrated manganese zinc iron oxide) microclusters on matrix thumbnail from the Plaka Mines, Laurium, Greece. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the image!
Row 10
Chalcophanite An excellent small cabinet specimen of sparkling chalcophanite and matte pyrolusite from La Union, Murcia, Spain. It has a Pareja Minerals tag. Thanks to Marvin Schwalb's auction on eBay for the specimen!	Chromite in Dunite Dunite, the non-gem massive granular tan to light green variety of olivine, often has members of the spinel group embedded within. This large cabinet specimen from the mountains of western North Carolina has hundreds of shiny black chromite (iron chromium oxide) octahedrons. Chromite forms two complete series, one with hercynite (iron aluminum spinel) and one with magnesiochromite (magnesium chromium spinel). It's also dimorphic with donathite. Chromite usually occurs in massive habit, e.g., as the matrix for zaratite. Thanks to Mike Streeter's auction on eBay for the specimen! Thanks also to Mike Streeter for the compositional update - this was originally thought to be spinel in dunite.	Chromite A miniature of rare chromite crystals in vugs with vesuvianite and grossular from Eden Mills, Lamoille County, Vermont. Thanks to Val Collins' auction on eBay for the specimen!
Row 11
Chromite A fascinating miniature of chromite nodules in matrix (great contrast!) from the Acoje Mine, Santa Cruz, Zambales Province, Luzon, Philippines. This locale is one of the major chromium mines in the world. The extreme closeup (larger image, bottom left) shows purple chroumium(VI) ion contamination of the matrix. It has a Burminco tag. Thanks to Jasun McAvoy's (Mineralman.com auction on eBay for the specimen and the image!	Columbite-Tantalite Columbite-tantalite is the generic name for unanalyzed members of the columbite/tantalite family (they're hard to distinguish without sophisticated tests) - this handsome thumbnail cluster comes from the Morro Redondo Mine, Coronel Murta, Minas Gerais, Brazil. Thanks to Alexander Falster's auction on eBay for the specimen and the image!	Coronadite A small cabinet chunk of brownish-black massive coronadite (a manganese lead - and usually barium and vanadium - oxide) from Inyo County, California. Thanks to Thomas Bee's auction on eBay for the specimen!
Row 12
Coulsonite A miniature of coulsonite (iron vanadium oxide, spinel family) crystals in magnetite from near the Buena Vista Hills, 32 km SE of Lovelock, Pershing County, Nevada. It forms an incomplete series with magnesiocoulsonite, its magnesium analog. Thanks to Emilie & Ron Kendig's auction on eBay for the specimen!	Cryptomelane A thumbnail of rare (for Pennsylvania) cryptomelane (a manganese potassium oxide) from the Wharton Mine, Mount Holly Springs, Cumberland County, Pennsylvania. Cryptomelane is under study as an ion-exchange adsorption agent for highly toxic cadmium from wastewater. Thanks to Ron Sloto's auction on eBay for the specimen and the image!	Diaspore Diaspore is one of the three aluminum (hydr)oxides (with boehmite and gibbsite) referred to as bauxite. Pale lavendar diaspore crystals comprise most of this small cabinet piece from (probably) the Chester Emery Mines, Chester, Hampden County, Massachusetts - it's from the collection of L. L. Hubbard, which dates it to the 1920s. Thanks to Thomas Bee's auction on eBay for the specimen!
Row 13
Diaspore A miniature of diaspore from Turkey. Thanks to Hasan Diker's (Lapidarydealers) auction on eBay for the specimen!	Diaspore A beautiful gemmy lavender diaspore crystal from Turkey. These are often sold as "Zultanite" or "Csarite" in the jewelry trade. Thanks to Bill Kohout's auction on eBay for the specimen and the image!	Diaspore, var. Mangan-diaspore This beautiful miniature of mangandiaspore (the manganese-rich variety of diaspore) from the Glossen Mine, Postmasburg, Griqualand West, South Africa also has some ephesite mica (closeup) on it. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!
Row 14
Feitknechtite A large thumbnail of brown massive feitknechtite (β-manganese(III) hydroxyoxide) with small flecks of white calcite from the Noda-Tamagawa Mine, Iwate Prefecture, Japan. It's a trimorph with groutite and manganite. Thanks to Reiner Mielke's auction on eBay for the specimen and the images!	Ferberite Ferberite's the iron-rich end of the ferberite - wolframite - huebnerite series. This ferberite cluster on muscovite is from the Yaogangxian Mine, Yizhang County, Hunan Province, China. The closeup (larger image, right) shows a small pocket of purple fluorites on the bottom. It also forms an incomplete series with sanmartinite, where zinc replaces part of the iron. Thanks to Dave Hayward at Lucky Strike Minerals for the specimen and the image!	Ferberite This ferberite from Ward District, Boulder County, Colorado occurs as a fine druse. Thanks to Frank Butler's auction on eBay for the specimen and the images!
Row 15
Feroxyhyte Feroxyhyte's an interesting mineral (iron hydroxyoxide); it only exists in an anaerobic environment. This thumbnail from the type locality of Kolomea, Ukraine has long since altered spontaneously to goethite. It's a trimorph with goethite and lepidocrocite and forms an incomplete series with akaganéite, where chlorine replaces some of the cations. Thanks to Ingo Drescher's auction on eBay for the specimen!	Ferrocolumbite A thumbnail chunky ferrocolumbite (once iron metaniobate, now an iron niobium mixed oxide) crystal collected in 1996 from the Coats Mine, Petaca district, Rio Arriba County, New Mexico. It forms two complete series, one with ferrotantalite and the other with manganocolumbite and an incomplete series with magnocolumbite. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen!	Ferronigerite-2N1S An excellent thumbnail of a hexagonal ferronigerite-2N1S (an aluminum tin iron zinc magnesium mixed oxide) crystal on matrix from the Stiepelmann Mine, Arandis, Swakopmund District, Erongo Region, Namibia. Thanks to Paolo Bracci's auction on eBay for the specimen and the images!
Row 16
Ferrotapiolite Ferrotapiolite is an iron manganese tantalum oxide with a trace of niobium - this rich miniature comes from the Zundum Mine, Pontal District, Minas Gerais, Brazil. It forms a complete series with manganotapiolite where the manganese content is greater than the iron. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen!	Fluornatromicrolite A rare new mineral in the microlite group, fluornatromicrolite (a bismuth, fluorine, and sodium-rich tantalum oxide) occurs as green isometric crystals, as in this micro of fluornatromicrolite in albite from the type locality of the Quixaba Mine, Frei Martinho, Paraíba, Brazil. Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen!	Franconite Franconite is what used to be called a niobate, a hydrated sodium salt of tetraniobic acid (Na2Nb4O11 · 9H2O). Chemists now consider most niobates (and related compounds) to be merely mixed oxides. This thumbnail is from Mont Saint Hilaire, Quebec, Canada. Thanks to PhelansFinds auction on eBay for the specimen!
Row 17
Franklinite and Willemite A small cabinet specimen of black octahedrons of franklinite (another iron zinc manganese oxide) and reddish-brown willemite (one of the zinc silicates) in white calcite from the co-type locality of Franklin, New Jersey. The willemite glows bright green and the calcite red under longwave UV.	Franklinite This miniature has lots of franklinite crystals, some green willemite, and one andradite garnet on a calcite matrix, also from Franklin. Thanks to Scott Stepanski's auction on eBay for the specimen!	Franklinite A miniature of radiating franklinite from the Siete Suyos Mine, Potosi, Bolivia. Thanks to Ken DeMary's auction on eBay for the specimen!
Row 18
Franklinite This miniature from Franklin, New Jersey has a fairly complex franklinite crystal. Thanks to Marvin Schwalb's auction on eBay for the specimen!	Franklinite A beautiful contrasty miniature of sharp franklinite crystals on bright red-orange fluorescing calcite (larger image, lower right) from the type locality of the Sterling Mine in Ogdensburg, New Jersey. Thanks to Charles Rosa's auction on eBay for the specimen!	Galaxite Galaxite's another member of the Spinel Group - this toenail of silvery-black galaxite (aluminum manganese magnesium oxide) is from the type locality of Bald Knob, Galax, Alleghany County, North Carolina. The larger image shows (closeup) tiny orange spessartines on the galaxite matrix. Thanks to Mike McDuffie's auction on eBay for the specimen!
Row 19
Gerasimovskite An excellent rich specimen of grayish-brown gerasimovskite (a hydrated niobium titanium manganese calcium oxide) platy crystals in matrix from the Umbozero mine, Alluaiv Mt, Lovozero Massif, Kola Peninsula, Murmanskaja Oblast', Russia. This specimen was identified by Dr. Igor Pekov. Gerasimovskite (once called niobobelyankinite) forms a series with manganbelyankinite, where the manganese content is higher. It is believed to have formed by the hydrothermal alteration of minerais of the murmanite-lomonosovite series. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the images!	Gibbsite Usually gibbsite is a nondescript, colorless, microcrystalline mineral - this specimen from the 2003 find at Baoshan, Yunnan Province, China consists of aqua-blue botryoidal gibbsite on matrix. When first found it was mistaken for smithsonite. It also fluoresces an odd olive-green under LUV. Gibbsite is a polymorph with bayerite, doyleite, and nordstrandite and comprises, along with boehmite and diaspore, the aluminum ore bauxite. Thanks to Larry & Amy Curtis' auction on eBay for the specimen!	Gibbsite An excellent, beautiful miniature of blue gibbsite from the 2012 find at the Hongsheke bauxite deposit, Yanshan County, Wenshan, Yunnan Province, China. I don't know what causes the blue color - the Hongsheke mineralization doesn't show any copper minerals that often account for blue colors. Thanks to Rob Lavinsky at The Arkenstone for the specimen and the images!
Row 20
Gibbsite An excellent miniature of yellow gibbsite from the active quarry at Mokrá, Zlutice, Karlovy Vary Region, Bohemia, Czech Republic. Thanks to Robert Vano's auction on eBay for the specimen and the images!	Goethite A miniature radiating crystal cluster of goethite (alpha-ferric hydroxyoxide) from Lake George, Park County, Colorado. It's a trimorph with feroxyhyte and lepidocrocite. Thanks to Ken DeMary's auction on eBay for the specimen!	Groutite Groutite, even though it sounds like a trademarked sealant, is the manganese analog of diaspore and goethite, MnO(OH). It's also a trimorph with manganite and feitknechtite. This thumbnail of tiny black groutite crystals in a white, pink, and green matrix is from Talcville, St. Lawrence County, New York. Ex: Fred D'Esopo Collection. Thanks to Emilie & Ron Kendig's auction on eBay for the specimen!
Row 21
Groutite This miniature of iridescent groutite crystals in matrix comes from the Zavalye graphite field in the Haivoron district, Kirovohrad Oblast', Ukraine. Thanks to Mirek Dorejko's auction on eBay for the specimen and the images!	Groutite A very good thumbnail of groutite and quartz crystals in matrix from the Robert Mine in the Cuyuna Range, Crow Wing County, Minnesota. These groutites from the early 80s (1981, here) are considered by some to be "best of species" specimens - this one was ex: Dennis Westman Collection and Mineral Zone dealer #9211. Thanks to Stephen Hernly's auction on eBay for the specimen and the images!	Hausmannite Hausmannite's a fairly rare (and hard) manganese oxide - this thumbnail (with white barite and pink andradite) is from the N'Chwaning Mine, Kuruman, South Africa. Thanks to Chris Korpi at Pangaea Minerals for the specimen!
Row 22
Hausmannite Another hausmannite specimen from N'Chwaning - this one's a small cabinet piece. Thanks to Rocko's auction on eBay for the specimen and the image!	Hausmannite An odd small cabinet specimen of massive hausmannite from (surprise, not South Africa!) the Cannon Mine in Stambaugh, Menominee iron range, Iron County, Michigan. Ex: Donald L. Schuder Collection (Purdue University). Thanks to David Schuder's auction on eBay for the specimen and the images!	Hematite This is a miniature of massive specular hematite (specularite) that I found in a former driveway. The other half of it was made into jewelry. Hematite (iron oxide) is found everywhere.
Row 23
Hematite More hematite - this miniature's from Bouse, Yuma County, Arizona. Thanks to Dan Wienrich at Dan & Jill Weinrich for the specimen and the image!	Hematite A small cabinet hematite cluster from the Bacino mine, Rio Marina, Elba Island, Livorno Province, Tuscany, Italy. Thanks to Rossano Carlini at E-Mineralsfor the specimen!	Hematite on Garnet A thumbnail of microcrystalline specularite coating a garnet from the Maynard Bixby Claim, Thomas Mountains, Utah. Thanks to Walter Mroch's (The Gem and Mineral Exploration Company) auction for the specimen!
Row 24
Hematite A beautiful 5 cm hematite mirror from the Pedra Preto Pit, Brumado, Bahia, Brazil. Thanks to Chris Korpi at Pangaea Minerals for the specimen!	Hematite on Quartz Clusters of beautiful specular hematite on beta quartz (more precisely, alpha quartz after beta quartz) and beige barite rosettes (larger picture, lower right) comprise this small cabinet piece from the Florence Mine, Egremont, Cumbria, England. The "beta quartz" are in hexagonal dipyramids (larger picture, upper right) with no prism faces in between - very different from ordinary alpha quartz. Thanks to Chris Korpi at Pangaea Minerals for the specimen!	Hematite Denny Mountain, in the North Cascades (King County) of Washington State was the home of this glitter-producing large cabinet specularite. Thanks to Joseph George's (Cascade Scepters) auction on eBay for the specimen!
Row 25
Hematite This large (19 cm) specimen of hematite crystals in matrix is from a highly unusual locality - the Atlas Mountains of Morocco. Thanks to David Jessey's auction on eBay for the specimen!	Hematite A single large (almost 5cm across) of hematite from Itibiara (Itaibiara), Bahia, Brazil. Mined 25-30 years ago, most of the faces have a matte finish but some still have a mirror-like luster. Thanks to Margaret Lidstrom's auction on eBay for the specimen!	Hematite after Siderite Hematite after siderite on quartz miniature from Sentinel Rock, El Paso County, Colorado. Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen!
Row 26
Hematite This thumbnail of hematite crystals from the N'Chwanning Mine in the Kalahari Manganese Fields of South Africa was too shiny for me to photograph! Thanks to Craig Ackermann's (KalahariMinerals.com) auction on eBay for the specimen and the image!	Hematite A compact heavy hematite rose miniature from the mid-2001 find in Jiang Xi Province, China. Thanks to James Bowers' auction on eBay for the specimen!	Hematite Beautiful small cabinet iridescent hematite from Marino, Isle of Elba, Italy. Thanks to Carl Bentley's auction on eBay for the specimen!
Row 27
Hematite A gorgeous hoppered hematite crystal (thumbnail) from Oaxaca, Mexico. Ex: Gene Meieran Collection. Thanks to Rob Lavinsky at The Arkenstone for the specimen and the image!	Hematite An excellent thumbnail floater of botryoidal (almost oolitic in size) hematite from the gravel roadbeds at Prince Sultan Air Base, Al-Kharj, Saudi Arabia. It looks very similar to the hematite from Tleta, Iroud, Morocco. The larger picture shows the others - two globular, a hemispherical, and two cylindrical specimens. Thanks to Yoly for the specimens!	Hematite An excellent miniature of bubbly hematite from near Bouse, Arizona. Thanks to Walter Mroch's auction on eBay for the specimen and the image!
Row 28
Hematite, var. Martite A small miniature of beautiful hematite crystal pseudomorphs (martite) on magnetite from the 2002 find in the inactive fumaroles in Patagonia, Argentina. Thanks to SoCal Nevada's auction on eBay for the specimen!	Hematite, var. Martite A old miniature of martite and yellow apatite on magnetite from Twin Peak, Millard County, Utah.	Hematite, var. Rainbow These natural aluminum-phosphate-coated specular hematites from a vertical five-foot-wide vein running about thirty feet up a face in an iron mine at Belo Horizonte, Minas Gerais, Brazil became a jewelry fad a few years ago. The defocused image (larger image, right) shows the colors better. Thanks to Darlene's auction on eBay for the specimen!

Row 29
Hercynite A large cabinet specimen of tiny grains of black magnetic hercynite (iron aluminum spinel) with phlogopite in a friable carbonatite matrix from the Kimzey Calcite Quarry, Magnet Cove, Hot Spring County, Arkansas. It forms three complete series; with chromite, gahnite, and spinel. Hercynite's named for the Hercynian Forest in ancient Bohemia (now Germany) where it was first found. Thanks to Alexander Falster's auction on eBay for the specimen!	Hetaerolite A small cabinet specimen of hetaerolite (manganese zinc mixed oxide) from the Carnahan Mine (1890's to about 1920) in the San Pedro Mountains of Santa Fe County, New Mexico. It forms an incomplete series with hausmannite, where manganese(II) replaces the zinc. Thanks to William Schwiner's auction on eBay for the specimen!	Heterogenite-3R A beautiful thumbnail of black heterogenite-3R (a cobalt hydroxyoxide) with green chrysocolla and blue azurite from Tuckerville, Hinsdale County, Colorado. It's the trigonal polytype of the hexagonal heterogenite-2H. Ex: Volkwein Collection # H1-15. Thanks to Dieter Obrecht's The NetMine auction on eBay for the specimen and the images!
Row 30
Hollandite A nice miniature of hollandite (a manganese barium oxide) from Rattlesnake Canyon, Socorro County, New Mexico. Recent anayses show a little bit of iron, lead, aluminum, and sodium present. Hollandite's structure is under study as a manganese-oxide-based nanofiber for VOC removal in air and arsenic removal in drinking water. Thanks to Wright's Rock Shop's table at the 2004 Carnegie Gem & Mineral Show for the specimen!	Hollandite A beautiful miniature of hollandite "icicles" from the Esperanza Mine, El Estrecho de San Gines, La Union, Sierra de Cartagena, Murcia, Spain. Thanks to Dieter Obrecht's The NetMine auction on eBay for the specimen and the images!	Hollandite in Quartz An excellent thumbnail of Madagascaran "star quartz" - quartz crystal with hollandite inclusions, probaly from Anketsaketsa, Ambatofinandrahana District, Amoron'i Mania Region, Fianarantsoa Province. Thanks to Bob Patak at Shadyside Mining for the specimen!
Row 31
Hollandite Another (and unusual) habit for hollandite - this micro has free=standing millimeter=sized crystals on matrix - from Ultevis, Lappland, Norrbotten, Sweden. Ex: Mineral Zone (10 / 2008). Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen and the images!	Hubnerite A nice hubnerite (manganese tungsten mixed oxide) crystal with attached fluorite and quartz from the Pasto Bueno district, Ancash Department, Peru. It was once considered to be manganese tungstate, but analyses have shown that there are no WO4 tetrahedra present.	Hubnerite The manganese-rich member of the wolframite series is hubnerite - this micro topped with quartz crystals is from the Black Pine Mine, Granite County, Montana. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the image!
Row 32
Hubnerite A very nice thumbnail of hubnerite from San Juan County, Colorado. Thanks to Frank P. Butler's auction on eBay for the specimen and the images!	Hubnerite An excellent thumbnail of stacked hubnerites from the mines in the Pasto Bueno District, Pallasca Province, Ancash Department, Peru Thanks to Saul Krotki's auction on eBay for the specimen and the images!	Hydrohetaerolite Hydrohetaerolite is a hydrated manganese zinc oxide "spinel wannabe" - this small cabinet piece comes from (probably) the co-type locality of the Passaic Pit, Sterling Hill, Sussex County, New Jersey. Thanks to Rick Dillinger's auction on eBay for the specimen!
Row 33
Hydropyrochlore An excellent sharp micro of tan hydropyrochlore (a complex niobium hydroxyoxide) from the type and only locality of the Lueshe Mine, Kivu, Democratic Republic of Congo. Thanks to Paolo Bracci's auction on eBay for the specimen and the image!	Ilmenite A shimmery gray small cabinet specimen of massive ilmenite (iron titanium oxide), now the most important titanium ore. This old specimen's from Kragerø, Telemark, Norway. Ilmenite forms two series; one with geikielite where magnesium, and pyrophanite where manganese replaces the iron. Thanks to Willis Williams' auction on eBay for the specimen!	Ilmenite Sometimes ilmenite fills in the cracks in quartz as in this cabinet specimen from the Davis Farm in Bethel, Windsor County,Vermont. Thanks to Eric Greene's (Treasure Mountain Mining) auction on eBay for the specimen!
Row 34
Ilmenite A nice miniature of compacted ilmenite crystals with some pyrite from Tahawus, Essex County, New York. Thanks to Val Collins' auction on eBay for the specimen and the image!	Ilmenite A beautiful rare ilmenite rosette micro from Mont St. Hilaire, Quebec, Canada. The photo was taken at 20X. Thanks to Chris Stefano's auction on eBay for the specimen and the image!	Ilmenite An excellent miniature of rare ilmenite in a quartz matrix from the famous Graves Mountain Mines in Lincoln County, Georgia. Thanks to Susan Matthews' (Apex Minerals) auction on eBay for the specimen and the images!
Row 35
Ilmenorutile A small cabinet specimen of black ilmenorutile (a titanium niobium iron oxide) in matrix from the South Platte district, Jefferson County, Colorado. It forms a series with struverite where tantalum replaces the niobium. Thanks to Alexander Falster's auction on eBay for the specimen!	Jacobsite A very rare thumbnail of sharp jacobsite octahedra on matrix from the N'Chwaning II Mine, Kalahari manganese fields, Northern Cape Province, South Africa. It's dimorphic with iwakiite and forms a series with magnetite. Thanks to Rob Lavinsky at The Arkenstone for the specimen and the image!	Jeppeite Tiny rough black jeppeite (a titanium, barium, potassium, iron mixed oxide) crystals in matrix comprise this micro from the type locality of the Walgidee Hills lamproite, Noonkanbah sheep station, Kimberley, Derby-West Kimberley Shire, Western Australia, Australia. Thanks to Paolo Bracci's auction on eBay for the specimen and the image!
Row 36
Kamiokite A miniature of very rare black kamiokite (an iron molybdenum oxide) in matrix from the Vrchoslav fluorite deposit, Krupka, Teplice, Krusné Hory (Erzgebirge), Bohemia, Czech Republic. Once classified with the molybdates, it is now a mixed-oxide mineral. Thanks to Thomas Bee's auction on eBay for the specimen and the images!	Koechlinite A pretty miniature of yellow koechlinite (a bismuth molybdenum oxide) on chrysocolla from the Inspiration Mine, near Miami, Gila County, Arizona. It also was classified as a molybdate but is now a mixed oxide. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!	Latrappite Another member of the Perovskite Group, latrappite is a niobium calcium (and a few other anions) oxide - this miniature of latrappite crystals in matrix is from Oka, Québec, Canada. Thanks to Alain Tiercelin's auction on eBay for the specimen and the image!
Row 37
Latrappite A sharp 4mm latrappite crystal from the St Lawrence Columbium Mine, Oka, Deux-Montagnes Co., Québec, Canada. This was collected in 2002 - the mine has since been depleted and no good specimens remain. Thanks to Jonathan Levinger's (Jonathan's Mineral Exchange) auction on eBay for the specimen and the image!	Lithiophorite A small cabinet specimen of black (slightly iridescent) lithiophorite (a manganese aluminum lithium hydroxyoxide) on dark-red chert from (probably) the Sausalito Road Quarry, Sausalito, Marin County, California. Thanks to Mike Keim at Marin Minerals for the specimen and the images!	Loparite A beautiful miniature interpenetration twin of loparite (a complex sodium cerium lanthanum calcium (meta)niobate-tantalate) on matrix from Khibiny, Kola Peninsula, Russia. In thin sections it's bright red (larger image, bottom right). Thanks to Dave Hayward at Lucky Strike Minerals for the specimen!
Row 38
Lueshite A sharp 5mm cube of lueshite (sodium metaniobate) from the type locality of Lueshe, Nord-Kivu, Republic of the Congo. The crystals rarely get better than this! It's a polymorph with isoueshite and natroniobite. Also, it's a member of the perovskite group. Thanks to Thomas Bee's auction on eBay for the specimen and the image!	Maghemite A large thumbnail of massive maghemite from Gara, Algeria, so named because it's a hematite dimorph with a magnetite structure; like magnetite, it's strongly magnetic. Synthetic maghemite is being studied as part of an electrically conductive and magnetizable film in nanocomposite structures. Thanks to Thomas Bee's auction on eBay for the specimen!	Magnesiochromite A small cabinet specimen of magnesiochromite (magnesium chromium oxide) with serpentine collected in the 1970s from the Wood's Chromite Mine, State Line Area, Pennsylvania. It forms two series, one with chromite and one with spinel. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen and the image!
Row 39
Magnesiocoulsonite Tiny black crystals of magnesiocoulsonite (magnesium vanadium oxde) and green chromium diopside in matrix comprise this micro from the type locality of the Pereval Marble Quarry, Sludyanka, Baikal area, Buriatia Republic, Transbaikalia, Eastern-Siberian Region, Russia. It's the magnesium analog of Systematic-Minerals.com auction on eBay for the specimen and the images!	Magnesionigerite-6N6S This micro has a grouping of deep orange magnesionigerite-6N6S crystal fragments in matrix (larger image). It's tagged as being from Luc Yen, Vietnam but MinDat only shows (two - one the type) Chinese localities. Magnesionigerite is an aluminum tin iron magnesium zinc oxyhydroxide and has iron and zinc analogs. It was formerly named pengzhizhongite-24R for Peng Zhizhong, the late Chinese mineralogist. Thanks to Paolo Bracci's auction on eBay for the specimen and the image!	Magnesiopascoite A micro of bright orange crystals of magnesiopascoite (a hydrated calcium magnesium decavanadate) on matrix from somewhere in Mesa County, Colorado. Magnesium replaces one (and only one) of the three calcium atoms in the structure so there is no complete series between it and pascoite. Thanks to Paolo Bracci's auction on eBay for the specimen and the image!
Row 40
Magnetite A museum size massive magnetite with pyrite and chalcopyrite from a banded iron formation in the Cambrian Deadwood Formation near Box Elder Creek, Nemo, Lawrence County, South Dakota. The closeup shows the pyrite veins. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!	Magnetite More magnetite - this small cabinet piece is crystalline magnetite on massive magnetite with a few small yellow sphalerites. It came from the ZCA Pierrepont Mine in Pierrepont, St. Lawrence County, New York. Thanks to Dave Hayward at Lucky Strike Minerals for the specimen and the image!	Magnetite This thumbnail of beautiful magnetite crystals is from the Blowout Pit, Iron Mountain, Iron County, Utah. Thanks to Bob Keller at the Arizona Mineral Company for the specimen and the images! Images copyrighted by the Arizona Mineral Company.
Row 41
Magnetite A miniature of sharp magnetite crystals in schist from Diamantina, Ouro Preto, Minas Gerais, Brazil. Thanks to Graeber & Himes' table at the 1999 Carnegie Gem & Mineral Show for the specimen!	Magnetite Millimeter-sized magnetite crystals adorn the twin dolomite spires on this small cabinet from Mexico. Thanks to Donna Lee Hanlon's (Donna's Treasures) auction on eBay for the specimen!	Magnetite A cabinet specimen of magnetite crystals in soapstone from the Old Talc Mine, North Windham, Vermont. Thanks to Scott Stepanski's auction on eBay for the specimen!
Row 42
Magnetite Nice octahedral magnetite crystals with adularia, actinolite and quartz miniature from the Gecko Prospect in Hidalgo County, New Mexico. Thanks to Tom Hales' (Museum Minerals) auction on eBay for the specimen!	Magnetite A beautiful magnetite twin thumbnail.	Magnetite Sharp shiny magnetite octahedra in a uralite matrix from the Calumet Iron Mine, Salida, Chaffee County, Colorado, one of the dassic localities for this combination. Uralite is a generic term for an amphibole pseudomorphed from a pyroxene, typically hornblende after augite - these are fairly long translucent green pinacoidally-terminated prisms, so the two minerals on this small miniature are probably different. Thanks to Ken DeMary's auction on eBay for the specimen!
Row 43
Magnetite Rarely, magnetite occurs in a cubic form - as in this micromount from the early 1990s find at the 2500' Level, ZCA's #4 Mine, Balmat, St. Lawrence County, New York. Thanks to Don Smoley's Minerals & Gems' table at the 2001 Carnegie Gem & Mineral Show for the specimen!	Magnetite A miniature of magnetite crystals on matrix from Mina Huaquio, Potosi, Bolivia - some of the crystals faces are very complex (larger image, right). Thanks to H M & D Minerals' table at the 2002 Carnegie Gem & Mineral Show for the specimen!	Magnetite From somewhere in Utah comes this miniature cluster of rough magnetite crystals. Thanks to Rohana Contessa's auction on eBay for the specimen!
Row 44
Magnetite A beautiful miniature of sharp magnetite crystals on massive magnetite from the Karzamkul deposit, Qostaney Oblysy, Kazakhstan. The crystals do have the brownish tint to them as shown in my photos. The larger iamge (bottom row) shows an unidentified (but likely a chlorite-group) green mineral. Thanks to Don Smoley's Minerals & Gems' table at the 2004 Carnegie Gem & Mineral Show for the specimen!	Magnetite A rare (rhombo)dodecahedral striated magnetite crystal thumbnail from Utah. Thanks to auction on eBay for the specimen and the images!	Magnetite, var. Titanomagnetite Titanomagnetite is the midmember of the magnetite-ulvöspinel series - this miniature of titanomagnetite in serpentine is from Dypingdal, Snarum, Modum, Buskerud, Norway. It's the most common magnetic mineral in seafloor basalts. Thanks to Thomas Bee's auction on eBay for the specimen and the image!
Row 45
Manganese Nodule There are a lot of these manganese (oxide) nodules (avg. metal composition 30%Mn 24%Fe 1%Ni 0.5%Cu 0.5%Co) on the ocean floor - this miniature came from a black smoker at 10° North latitude, depth 17,000 ft, North Pacific Ocean, collected by Glomar Explorer. Thanks to Jennings "Beau" Gordon's (Jendon Minerals) auction on eBay for the specimen!	Manganite An excellent miniature of crystalline manganite (α-manganese(III) hydroxyoxide) on massive manganite from the Caland Pit, Atikokan, Hutchinson Township, Ontario, Canada - when plentiful, it's an ore of manganese. It was collected in August 1985. Thanks to Brett Shafer at The Mineral Vug for the specimen! Thanks also to Bill Morgenstern for the collection date!	Manganite This beautiful large miniature of botryoidal manganite is from the N'Chwaning Mine, Kuruman, South Africa. Thanks to Craig Ackermann's (KalahariMinerals.com) auction on eBay for the specimen and the images!
Row 46
Manganite An excellent cabinet specimen of manganite and minor hematite on matrix from the Wessels Mine, Hotazel, Kalahari manganese fields, Northern Cape Province, South Africa. Thanks to Kathy Wittwer's auction on eBay for the specimen and the images!	Manganocolumbite A thumbnail of rare (for the locality) manganocolumbite (once a manganese metaniobate, but now a mixed oxide of manganese, iron, niobium, and tantalum) from the Dunton Quarry, Plumbago Mountain, Newry, Oxford County, Maine. It forms a complete series with manganotantalite and ferrocolumbite and an incomplete series with magnocolumbite. Ex: Brownie Thompson collection. Thanks to Tom Klinepeter's auction on eBay for the specimen!	Manganostibite in Iwakiite A rare thumbnail of gray manganostibite (manganese iron antimonate) in dark-green iwakiite (a manganese iron oxide and a dimorph of jacobsite) from Nordmark, Filipstad, Sweden - the tag only specified Nordmark; the specimen may be from either Jakobsberg or even the type locality of the Moss Mine. Some references add a (neso)silicate cation to the composition but for now I'm keeping it here with the oxides. Thanks to Marcelo Behar's auction on eBay for the specimen!
Row 47
Manganotantalite An excellent twinned thumbnail of manganotantalite collected in 2002 from the Alto de Furnas Mine, Equador, Rio Grande de Norte, Brazil. It's a dimorph of Manganotapiolite and forms series with manganocolumbite and ferrotantalite. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen!	Manjiroite A miniature of massive manjiroite (sodium manganese oxide) from Tombstone, Cochise County, Arizona. It's a member of the hollandite subgroup of the cryptomelane group - the hollandite group of minerals may have an application as nuclear waste-disposal storage materials. The eight MnO2 octahedra form small square zeolite-like tunnels, which, like zeolite, can trap other chemicals. From the Collection of Joe Cilen of New Jersey, originally purchased from W. D. Christanson. It probably was originally verified by Dr. Sidney Williams. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen!	Montroydite Tiny reddish crystals of montroydite (mercuric oxide) on matrix comprise this miniature from somewhere in California - the label is not specific but it looks like Clear Creek, New Idria District, Diablo Range, San Benito County material. Montroydite can also be yellow is the crystal size is smaller (or powdered). It decomposes upon heating above 500°C to form mercury and oxygen. Thanks to John Green's auction on eBay for the specimen!
Row 48
Mopungite Mopungite's a rare sodium antimony hydroxide - this capsule's from the type locality of Green Prospect, Churchill County, Nevada. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!	Mopungite A micro of red mopungite on matrix from the Le Cetine MineChiusdino, Siena Province, Tuscany, Italy. Thanks to Marco Poli's auction on eBay for the specimen and the close-up image!	Mopungite Another Le Cetine micro of mopungite on matrix - this time it's mostly a white crust. Thanks to Chris Stefano's auction on eBay for the specimen and the close-up image!
Row 49
Mroseite White patches of mroseite (a calcium tellurium mixed-oxide, once considered a tellurite-carbonate) on matrix comprise this micro from the T. E. I. pit, Tombstone District, Tombstone Hills, Cochise County, Arizona, Thanks to Paolo Bracci's auction on eBay for the specimen and the image!	Nolanite A micro of blackish-brown nolanite (a vanadium, iron, titanium oxyhydroxide) from the Srednyaya Padma mine, Karelia, Russia. Some references show a trace of aluminum as well. Australian nolanites also include tin and zinc. A synthetic nolanite (Fe2.5V+41.5V+35.6O16) shows promise in the design of data storage devices and temperature-sensitive sensors. Thanks to Jacek & Jaroslaw Skupienski's (Geo-Trader) auction on eBay for the specimen and the images!	Nsutite Nsutite's another one of the many manganese oxide / hydroxide minerals and its synthetic version, like rancieite, is used as an alkaline battery electrode. This small cabinet chunk of pure nsutite comes from the type locality, the Nsuta Mine, Ghana. Thanks to Thomas Bee's auction on eBay for the specimen!
Row 50
Omsite An excellent thumbnail of sub-millimeter yellow discoidal plates of omsite (a nickel, iron, antimony hydroxide) on matrix from the type and only locality of Oms, Pyrénées-Orientales, Languedoc-Roussillon, France. It's a member of the cualstibite group and the hydrotalcite supergroup. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the images!	Perovskite A large thumbnail of beautiful blue-black "octahedrons" (actually, they're orthorhombic bipyramids, but the lengths of the three axes are nearly equal so the crystals appear "cubic") of perovskite, calcium metatitanate, on matrix from the Kola Peninsula, Russia. That nearly cubic structure is very temperature dependent and perovskite materials have wide applications as sensors and actuators. Thanks to the MFG Auction Co.'s auction for the specimen and the image!	Pseudobrookite Pseudobrookite is a rare iron titanium oxide - it forms an incomplete series with armalcolite (most of the iron is replaced by magnesium). This thumbnail is probably from the Kovdor massif, Kola Peninsula, Russia.
Row 51
Psilomelane Psilomelane (now called romanèchite) often occurs in a beautiful dendritic habit, as in this old small cabinet specimen from Barstow, California. Thanks to Willis Williams' auction on eBay for the specimen!	Pyrolusite A miniature of compact, fibrous pyrolusite (manganese dioxide) from the Florida Mountains in Luna County, New Mexico. Pyrolusite is trimorphic with akhtenskite and ramsdellite and forms incomplete series with nsutite and vernadite. Thanks to Roxanna Wright's auction on eBay for the specimen!	Pyrolusite a cute miniature of pyrolusite (altered from manganite) from Socorro County, New Mexico. Thanks to Walter Mroch's auction on eBay for the specimen!
Row 52
Pyrolusite An excellent miniature of fibrous and massive pyrolusite from the Taylor Mine, near Alberta, Baraga County, Michigan. Collected in 2001 by Mike Basal. Thanks to Mike Basal's (From My Collection To Yours) auction on eBay for the specimen and the image!	Pyrolusite, var. Polianite Pyrolusite rarely forms crystals, when it does it's called "polianite". This thumbnail's from the Kisenge Mine, Democratic Republic of the Congo. The name is from the Greek "to become gray" in allusion to the silvery metallic luster. Thanks to Don Smoley's Minerals & Gems' table at the 2001 Carnegie Gem & Mineral Show for the specimen!	Ramsdellite Ramsdellite's the second trimorph of pyrolusite (very rare akhtenskite's the third) - this miniature is from the Mistake Mine in Yavapai County, Arizona. The back side is partially pseudomorphed to dusty gray pyrolusite. Ramsdellite forms incomplete series with nsutite and vernadite. Thanks to Richard Dale's (Dale Minerals International) auction on eBay for the specimen and image!
Row 53
Ramsdellite This thumbnail of sharply crystallized ramsdellite with pyrolusite is also from the Mistake Mine. Thanks to the Carnegie Natural History Museum Store for the specimen!	Ramsdellite A small miniature of ramsdellite and limonite from the type locality of the Lake Valley District, Sierra County, New Mexico. Thanks to Ted French's auction on eBay for the specimen!	Ramsdellite A larger excellent miniature of radiating and acicular ramsdellite also from the type locality. Thanks to Kevin Boulter's auction on eBay for the specimen and the images!
Row 54
Ramsdellite A fascinating thumbnail of ramsdellite after goethite after calcite from Santa Eulalia, Chihuahua, Mexico. Thanks to Kevin Boulter's auction on eBay for the specimen and the images!	Rancieite This small thumbnail of rancieite-coated calcite comes from the Verona Province in Italy. Synthetic rancieite-type compounds are being studied as electrodes for lithium batteries. Rancieite (a hydrated calcium manganese oxide) forms a series with takanelite, where cobalt replaces the calcium. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen!	Romanechite Romanechite is the correct name for what used to be called psilomelane, one of the many manganese oxides (a hydrated manganese barium hydroxyoxide), and is an important ore of manganese. This miniature's from the Black Beauty Mine, New Mexico. Thanks to Brian McManus at the Pebble Peddler for the specimen!
Row 55
Romeite Romeite is another of what used to be called an antimonate - now it's just a mixed oxide of antimony, iron, calcium, titanium, and manganese. This thumbnail of brown octahedral romeite crystals in matrix comes from the type locality of the Praborna Mine, Aosta Valley, Piedmont, Italy via the collection of Daniele Respino. Thanks to Tony Jones' auction on eBay for the specimen!	Rutile Rutile is titanium dioxide - it's an ore for that (used in white paints for superior "hiding power") and an ore of titanium. This miniature comes from the Magnet Cove Ti-Corp Mine in Magnet Cove, Hot Spring County, Arkansas. Thanks to Dan Wienrich at Dan & Jill Weinrich for the specimen and the image!	Rutile on Hematite Rutile often grows on hematite, as in this thumbnail from Novo Horizonte, São Paulo, Brazil.
Row 56
Rutile These are unusual elongated crystal sections and sagenitic forms of rutile from an unlikely place - an alpine cleft (Agua Calgada, Fraguita) in the normally barren Atacama Desert region of Chile. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!	Rutile A beautiful 60° "elbow" rutile twin discovered in December of 1998 near the city of Diamantina in Minas Gerais, Brazil. Thanks to MINERALMINERS.COM for the specimen!	Rutile A miniature of beautiful red rutile on dark green muscovite from Yates Brooks Farm, Cleveland County, North Carolina. Thanks to Shields Flynn at Trafford | Flynn for the specimen and the image!
Row 57
Rutile Another miniature of rutile on muscovite from the same location - there's more rutile and the muscovite's a lighter shade of green and less compact. Thanks to Dan Wienrich at Dan & Jill Weinrich for the specimen and the image!	Rutile A beautiful 120° "knee" rutile twin thumbnail from (probably) Diamantina, Minas Gerais, Brazil. Thanks to Walter Mroch's (The Gem and Mineral Exploration Company) auction for the specimen and the image!	Rutile An excellent rutile crystal on matrix thumbnail from MacGregor Lake, Quebec, Canada. Thanks to Doug Miller at Northern Lights Minerals for the specimen and the image!
Row 58
Rutile A very nice rutile crystal with kyanite and pyrophyllite (bottom, larger picture) on a quartzite matrix (miniature) from Graves Mountain, Lincoln County, GA. Thanks to Richard Jacquot's auction on eBay for the specimen!	Rutile More Graves Mountain rutile - this time with kyanite and pyrophyllite on a quartzite matrix (miniature). Thanks to Drexel Pitts' auction on eBay for the specimen!	Rutile A complex thumbnail cluster of rutile crystals from Graves Mountain, Lincoln County, Georgia. Thanks to Stan Perry's (Our Gangue Minerals) auction on eBay for the specimen and image!
Row 59
Rutile A small cabinet specimen of rutile from Graves Mountain - these crystals are very well defined (and big!). Thanks to Mike Shell's auction on eBay for the specimen!	Rutile A box of 60 or so centimeter-sized rutile crystals from Stoney Point, Alexander County, North Carolina - collected in the 1880s by Dr. Hidden and obtained from the Maxie McNeil holdings. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!	Rutile A cabinet size specimen of unusually large (for the state) elbow-twinned deep red rutile crystals in a micaceous matrix from a mountain behind an old farm in rural Bethel, Windsor County, Vermont - collected by Eric Greene in 1998. Thanks to Eric Greene's (Treasure Mountain Mining) auction on eBay for the specimen and the image!
Row 60
Rutile A beautiful micromount rutile cluster from Bahia, Brazil. Thanks to Frank P. Butler's auction on eBay for the specimen and the image!	Rutile on Hematite A gorgeous miniature of rutile on hematite on champagne smoky quartz from the Swiss Alps. Thanks to Jose Manuel Teodoro's auction on eBay for the specimen and the images!	Senarmontite A very nice 4mm senarmontite (antimony oxide) from the type locality of Djebel Haminate Mine, Ain Beida, Constantine, Algeria. It's dimorphous with valentinite. Thanks to Jan Garland's (Fine Rocks) auction on eBay for the specimen and the images!
Row 61
Sidwillite An excellent micro of light-yellow sidwillite (molybdenum trioxide dihydrate) on a quartz matrix from the type locality of Lake Como, San Juan County, Colorado. This specimen is from the Colorado suite of the Robert Jenkins II Collection. Thanks to Jasun McAvoy's (Mineralman.com) auction on eBay for the specimen and the images!	Simpsonite Simpsonsite's a tantalum aluminum niobium hydroxyoxide (some references throw in a fluoride ion) - this thumbnail's from Alto das Furnas Mine, Equador, Rio Grande do Norte, Brazil. Thanks to Alexander Falster's auction on eBay for the specimen!	Spinel Microscopic black spinel (magnesium aluminum oxide) crystals on these micromounts from Monte Somma, Vesuvius, Naples, Campania, Italy. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!
Row 62
Spinel More spinel - this deep pink miniature's from Mogok, Burma, one of the best locales for gem-quality spinels. Thanks to Chris Korpi at Pangaea Minerals for the specimen!	Spinel This complex black spinel crystal thumbnail comes from an area near MacDonald Island, Baffin Island, Nunavut, Canada. Thanks to Doug Miller at Northern Lights Minerals for the specimen!	Spinel A thumbnail of a deep blue spinel octahedron from the Crazy Sphinx Mine, near Helena, Lewis and Clark County, Montana. Thanks to Jeff Schlot at Crystal Perfection for the specimen!
Row 63
Spinel Another spinel from Mogok, Burma - this miniature's a bit redder than my other one. Thanks to Kevin Ward at the The Mineral Gallery for the specimen and the image!	Spinel Spinel comes in many colors - this medium-violet thumbnail's also from Mogok. Thanks to Frank P. Butler's auction on eBay for the specimen and the images!	Spinel A nice sharp, blue spinel crystal on matrix from the unusual location (for spinel) of Crazy Horse Claim, Helena, Montana. Thanks to Dave Bunk (Dave Bunk Minerals) auction on eBay for the specimen!
Row 64
Spinel A gorgeous sharp rose spinel (0.85 ct, 5.3x6.2 mm) from Burma. Thanks to Mark Steven's auction on eBay for the specimen!	Spinel (synthetic) This is a small cabinet specimen of incredibly sharp synthetic spinel with a C & J Rocks, Gems & Fossils label. It looks like a miniature blue fir landscape! Thanks to Jeff & Heather McCammon's (Second Nature Colorado) auction on eBay for the specimen and the image!	Spinel A miniature of tiny sharp blue spinels in a marble skarn matrix from the Northern Pirin Mountains in western Bulgaria. Thanks to Emil Stoyanov's auction on eBay for the specimen and the image!
Row 65
Spinel An excellent miniature of a bright blue color-change (larger image, right) spinel on a calcite matrix from Afghanistan. There's also an unidentified gemmy mineral present (larger image, bottom left). Thanks to Jan Garland's (Fine Rocks) auction on eBay for the specimen!	Spinel A fascinating miniature of red and green spinels in matrix from Mogok, Myanmar (Burma). One of the spinels is both colors! Thanks to Sieghard Ellenberger's auction on eBay for the specimen and the images!	Spinel, var. Chromspinel Chromium-tinted everything (spinel, diopside, and grossular) in this thumbnail from the Jeffrey Mine, Asbestos, Quebec, Canada. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!
Row 66
Spinel, var. Pleonaste Opaque black spinel (often called pleonaste - iron replaces some of the magnesium) on serpentinized forsterite in this miniature from the Parker Mine, Notre Dame de Laus, Quebec, Canada. Thanks to Darrel Merke's auction on eBay for the specimen and the image!	Squawcreekite Tiny orange crystals of squawcreekite, an iron antimony tin oxide, on a thumbnail matrix from the type locality of the Squaw Creek Tin Mine, Catron County, New Mexico. Different references give different compositions for squawcreekite (tungsten or titanium in place of tin) - some even consider it to be the same as tripuhyite. Thanks to Alexander Falster's auction on eBay for the specimen!	Srebrodolskite A micro of tiny brownish platy srebrodolskite (a calcium ferrate or calcium iron oxide) crystals in a xenolite matrix from Kloch, Bad Radkersburg, Steiermark, Austria. It forms a series with brownmillerite where Aluminum replaces some of the iron. This is from the 2010 find there and has been confirmed by analysis. Thanks to Csanad Loranth's auction on eBay for the specimen and the images!
Row 67
Stannomicrolite An excellent thumbnail of deep-yellow stannomicrolite (essentially a tin tantalum hydroxyoxide) crystals (larger image, center) nestled in a stokesite cluster from the Urucum Mine, Galilea, Minas Gerais, Brazil. There's also a tiny but sharp hexagonal unidentified crystal (larger image, bottom). Thanks to John Veevaert at Trinity Minerals for the specimen!	Stetefeldtite A miniature of black stetefeldtite (a basic silver meta-antimonate) in quartz pockets from the Belmont District in Nye County, Nevada - it may be type locality material from the Combination claim there. Stetefeldtite needs more work done on both its composition and structure - some references consider it to be a silver-bearing variety of romeite. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen and the image!	Stibiconite after Stibnite San Luis Potosi, Mexico is known for its rare stibiconite (antimony hydroxyoxide) pseudomorphs after stibnite. This small cabinet piece dates from the 1950s. Thanks to Leland Goodwin's auction on eBay for the specimen!
Row 68
Stibiotantalite Stibiotantalite's an antimony tantalum columbium oxide. This miniature's from the famous Himalaya Mine, in San Diego County, California and it and some lepidolite are riding on a smoky quartz point. It forms a complete series with stibiocolumbite and an incomplete series with bismutotantalite. Synthetic members of the stibiotantalite family may have application as ferroelectric (thin-film) memory devices. Thanks to Marcus Origlieri at The Mineral Zone for the specimen and the image!	Stibivanite A micro of greenish-yellow stibivanite (antimony vanadium oxide) needles on matrix from the type locality of the Consolidated Durham Mines and Resources Ltd. Mines, Lake George, York County, New Brunswick, Canada. It used to be considered a V+5 vanadate. Thanks to Paolo Bracci's auction on eBay for the specimen and the image!	Struverite This micro of a sharp crystal of struverite on matrix is from the Sahatany Valley in Central Madagascar. Struverite used to be considered a tantaloferric variety of rutile but is now the tantalum endmember of the struverite - ilmenorutile (niobium endmember) series. Thanks to Krzysztof Dembicz's auction on eBay for the specimen and the images!
Row 69
Tegengrenite A miniature of tiny red tegengrenite (an antimony manganese magnesium zinc oxide with trace titasnium and silicon) crystals (larger image, center, bottom) in matrix from the type locality of Jakobsberg near Filipstad, Värmland, Sweden. Thanks to Ingo Drescher's auction on eBay for the specimen!	Todorokite on Colemanite Todorokite is a hydrated manganese-IV manganese-III mixed oxide (with a few other anions thrown in; most references now give (Ca, Na, K).3-.5[Mn(IV), Mn(III), Mg]6O12·3-4.5H2O). This miniature from the Corkscrew Mine, Death Valley, Inyo County, California occurs as a brownish-black coating (and a few tiny crystals) on colemanite crystals. Thanks to Jan Garland's (Fine Rocks) auction on eBay for the specimen and the images!	Todorokite Another todorokite - this miniature looks like it comes from the ocean. The tag says "Peru" which probably refers to the Peru Basin (southeast Pacific Ocean) as a lot of todorokite occurs as part of deepsea manganese nodules and near-shore rock coatings. Synthetic todorokite is used as a catalyst and as a large zeolite-like "framework hydrate" filter for environmental heavy metal trapping. Thanks to Artemio Rocha's auction on eBay for the specimen and the images!
Row 70
Trevorite Tiny, sharp, and lustrous black octahedrons of trevorite (iron nickel spinel) in a green willemseite (nickel magnesium talc) matrix from the type locality for both minerals - the Bon Accord Nickel Deposit, near the Scotia Talc Mine, Barberton Mountain, Mpumalanga Province, South Africa. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!	Tripuhyite A small cabinet chunk of chalcedony and limonite hosts a bright! chartreuse swath of tripuhyite, a mixed oxide of iron and antimony (what used to be called an iron metaantimonate). It comes from the McDermitt Mine in Humboldt County, Nevada. Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen!	Tungstite Yellow tungstite (tungsten trioxide monohydrate) on scheelite from Canaan, Pikikiruna Range, Nelson, New Zealand. Thanks to Dave Buchan's auction on eBay for the specimen and the images!
Row 71
Turgite Turgite (or hydroxyhematite, 2Fe2O3 . H2O), named after the copper mines at Turginsk in the Russian Urals, is formed when a microscopically thin layer of hematite undergoes hydration. The beautiful iridescent bands are caused by light interference - the same happens with oil slicks on pavements. This miniature's from Sierra Mojada, Coahuila, Mexico. Thanks to Brett Shafer at The Mineral Vug for the specimen!	Turgite This turgite miniature's from Graves Mountain, Georgia. Thanks to Carl Bentley's auction on eBay for the specimen!	Valentinite These two (larger picture) miniatures of white valentinite (antimony oxide and a dimorph of senarmontite) on matrix are from the famous, long-abandoned mine at Pezinok, Slovakia. Thanks to Chris Auer's (Eureka Micromounts) auction on eBay for the specimen!
Row 72
Varlamoffite Varlamoffite, considered by some to be merely a variety of cassiterite, is a hydrated tin iron oxide. It's a weathering product of cassiterite - this miniature of golden tan varlamoffite on matrix comes from the famous Hingston Down Quarry, Hingston Down, Cornwall, England. Thanks to Brian McManus' (Pebble Peddler) auction on eBay for the specimen and the image!	Vernadite A miniature of feathery black streaks of vernadite (another hydrated manganese iron oxide) in calcite from Tombstone, Arizona. Ex: Joe Cilen Collection, purchased from Dick Hauck in June 1989 and probably identified by Dr. Sidney Williams. Vernadite also occurs on seafloor crusts where its negatively-charged surface aids the adsorption of large quantities of economically important metals (cobalt, nickel, zinc and thallium) from ocean water onto the crust surfaces. (A positively-charged amorphous iron oxyhydride does the same for copper, lead, titanium, molybdenum, arsenic, vanadium, tungsten, zirconium, bismuth and tellurium.) Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen!	Wodginite This is a rough thumbnail crystal of wodginite from Sapucaia do Norte, Galiléia, Minas Gerais, Brazil. It's a rare tantalum manganese tin niobium iron oxide. Wodginite forms a complete series with titanowodginite and incomplete series with ferrotitanowodginite, ferrowodginite, and lithiowodginite. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!
Row 73
Wodginite A sharp lustrous 1.6cm wodginite crystal from the 1980s find at the Jabuti Mine, São Geraldo do Baixio, Doce valley, Minas Gerais, Southeast Region, Brazil. Upon analysis these crystals are epitaxial wodginite over a tiny cassiterite core. Thanks to Ricky Houck's auction on eBay for the specimen and the images!	Wolframite A beautiful wolframite crystal with attached quartz from China. Wolframite is the midmember of the ferberite-hubnerite series and is often used generically for all three. Thanks to Miao Yang's auction on eBay for the specimen!	Wolframite and Scheelite Two pounds of milky quartz, arsenopyrite, lavender fluorite, tan scheelite, and white calcite on a wolframite matrix also from the Yaogangxian Mine in China. An impressive and fascinating specimen. Thanks to Miao Yang's auction on eBay for the specimen and image!
Row 74
Zincochromite A millimeter-sized flake of zincochromite (zinc chromium oxide hydroxide with trace magnesium and tin) from the type locality of Lake Onega, Karelia Republic, Russia. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen!	Zinconigerite-6N6S Tiny zinconigerite-6N6S (an aluminum zinc iron oxide) crystals on matrix from the Three Aloes (tantalite) Mine, Uis pegmatites, Uis, Damaraland District, Kunene Region, Namibia. Note that MinDat does not yet show zinconigerite from this location, only ferronigerite - see the comments on the above MinDat page. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen and the image!	Zirconolite There are two polytypes of tiny dark zirconolite (a calcium zirconium titanium oxide) crystals (rhombic and trigonal) on this sanidine matrix miniature from Castellaccio di Petrignano, near Vetralla, Viterbo, Lazio, Italy. Note that MinDat does not show zirconoloite polytypes from this locale. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen!

maintained by: Alan Guisewite

Last Update 11 Apr 2015