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My Mineral Collection, Systematic Nesosilicates Page

These are my nesosilicates. Nesosilicates are the simplest silicates - orthosilicate (SiO4) tetrahedrons unbonded to each other. Because of the nesosilicates' hardness, higher desnity than other silicates, range of colors, and (often) transparency, a lot of them are used as gems. In the nesosubsilicates, tetrahedra are periodically bonded to each other but not throughout the entire structure - think of them as existing between the neso and soro silicates.
Nesosilicates on Other Pages
See my garnet pages.

Also, see peridot, topaz, and zircon on my gemstones page.

See more vuagnatite on my copper minerals page.

Wherryite's on my lead minerals page.

Clinohedrite and willemite are on my zinc minerals page.

Specimens on This Page
(links take you to either the first or only specimen)

30 Rows

Afwillite

A miniature of rare afwillite (calcium hydroxysilicate) from the Crestmore Quarry, Riverside County, California. Afwillite also occurs in some hydrated Portland Cement mixtures. Ex: Larner R. Peak (1978) & David M. Shannon Collections.

Thanks to Kim & Cindy Strange's auction on eBay for the specimen and the image!

Alleghanyite

This thumbnail of pink alleghanyite (a manganese hydroxysilicate) comes from its type locality, Bald Knob, Alleghany County, in North Carolina. Alleghanyite's also a member of the humite group and dimorphic with ribbeite.

Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen and the image!

Andalusite

This gemmy crystal of green (although my camera likes to change it to red) andalusite (a trimorph with kyanite and sillimanite) is from Minas Gerais, Brazil.

Thanks to Mike Keim at Marin Minerals for the specimen and the image!

Row 2

Andalusite,
var. Chiastolite

Sometimes andalusite crystals occur in the variety known as chiastolite. The dark crosses are caused by incorporated inclusions during crystallization.

Thanks to Frank P. Butler's auction on eBay for the specimen!

Andalusite,
var. Chiastolite

Here's a cabinet specimen of many chiastolites in matrix from Westford, Hampden County, Massachusetts. It's from the J.W.V. Rawlings collection.

Thanks to Thomas Bee's auction on eBay for the specimen and the images!

Bakerite

An old miniature of massive bakerite (calcium borosilicate) from probably the type locality of the Corkscrew Mine, Corkscrew Canyon, Furnace Creek District, Death Valley, Inyo County, California. The original label (from W. Scott Lewis) just says Death Valley (larger image, bottom right), but it looks like the type locality material.

Thanks to Vince Olsovsky's auction on eBay for the specimen and the images!

Row 3

Bismutoferrite

Once classified as a phyllosilicate, this chartreuse crust of bismutoferrite (a bismuth iron hydroxysilicate) is now considered a nesosilicate. This miniature comes from Smrkovec, Bohemia, Republic of Czechoslovakia. It forms an incomplete series with chapmanite where antimony replaces some of the bismuth. There's a few other minerals here, including a transparent orange unidentified one (larger image, bottom panel).

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the image!

Bultfonteinite

Showing one of the three habits of bultfonteinite (a calcium fluorohydroxysilicate) from the Kalahari, this thumbnail botryoidal cluster is from the N'Chwaning Mines in South Africa. I don't know what the dark-brown mineral other than it's proably a manganese one.

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!

Bultfonteinite

The second habit is shown in this beautiful miniature of clustered acicular bultfonteinite from the Wessels Mine in South Africa. Here the cluster colrs vary from colorless through a light rusty-red. Bultfonteinite's third habit usually occurs with poldervaartite.

Thanks to Evan Wiley's auction on eBay for the specimen and the images!

Row 4

Cerite-(Ce)

A miniature (but heavy!) granular cerite (a cerium iron hydroxysilicate and the major ore of cerium) with calcite from Humammi, Oarus, Bolivia. It forms a series with Cerite-(La) where lanthanum (and calcium) replace some some of the cerium.

Thanks to Ken DeMary's auction on eBay for the specimen!

Cerite-(Ce)

A miniature of massive reddish-brown chunks of cerite in matrix from the type locality of the Bastnäs Mine, Riddarhyttan, Västmanland, Sweden.

Thanks to Tony Jones' auction on eBay for the specimen and the image!

Chapmanite

Once considered a phyllosilicate, chapmanite (an antimony iron hydroxysilicate) is now classified a neso(sub)silicate and forms an incomplete series with bismutoferrite, where bismuth replaces the antimony. This thumbnail of earthy yellow-green chapmanite is from the Cordero Mine (McDermitt Mine) in Humboldt County, Nevada.

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen and the image!

Row 5

Chloritoid

An old (acquired in 1934 from Minerals Unlimited) miniature of green chloritoid (an aluminum iron magnesium manganese hydroxysilicate) on matrix from the Humboldt Mine, Humboldt, Eagle River, Keweenaw County, Michigan. The Humboldt Mine was one of the more obscure copper mines in the region and only operated for about a year sometime in the 19th century. Chloritoid forms two series; one with magnesiochloritoid where magnesium replaces the iron and manganese, and ottrelite where manganese predominates.

Thanks to Kim & Cindy Strange's auction on eBay for the specimen and the image!

Chondrodite

Yellow chondrodite in calcite from the Limecrest Quarry, Sparta, Sussex County, New Jersey. The closeup shows some small graphite crystals on the back. Chondrodite's a member of the humite group.

Thanks to Scott Stepanski's auction on eBay for the specimen and the image!

Chondrodite

A miniature of chondrodite crystals in calcite from Mogok, Burma (Myanmar).

Thanks to Rob Lavinsky at The Arkenstone for the specimen and the image!

Row 6

Clinohumite

A miniature of orange clinohumite (a magnesium iron hydroxyfluosilicate) crystals in matrix from Benalmádena, Málaga, Andalusia, Spain. There's also a few brownish-black and reddish-violet spinels present (larger image, bottom row).

Thanks to William Kohout's auction on eBay for the specimen!

Datolite

Datolite, usually found as crystals, occurs in nodules only in Michigan's Upper Peninsula. This mauve miniature comes from the Caledonia Copper Mine located in Ontonagon County in the UP of Michigan.

Thanks to Steve Hecht's auction on eBay for the specimen!

Dumortierite

Lavender dumortierite from the Rochester District near Lovelock, Nevada.

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!

Row 7

Dumortierite

More dumortierite - this one's from Dehesa, San Diego County, California. Dumortierite's used for making spark plug insulators and other ceramic items.

Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen!

Dumortierite

More dumortierite - this bright blue miniature is from Urungwe, Zimbabwe. One of the closeups (larger image, center) shows a cluster of translucent crystals.

Thanks to Mike Keim at Marin Minerals for the specimen!

Dumortierite

A sawn chunk of blue layered dumortierite from Minas Gerais, Brazil.

Thanks to Mike Keim at Marin Minerals for the specimen!

Row 8

Dumortierite

Sometimes dumortierite can be a beautiful deep blue, as in this tumbled thumbnail from Madagascar.

Thanks to Wright's Rock Shop's table at the 2003 Carnegie Gem & Mineral Show for the specimen!

Dumortierite

Dumortierite and quartzite are often called "blue aventurine" - this miniature's from India.

Thanks to Thomas Anthony's auction on eBay for the specimen!

Dumortierite

An absolutely gorgeous large-cabinet polished end cut of dumortierite. This 3lb+ specimen comes from South Africa, probably the N'Rougas Suid farm, Kenhardt District, Namaqualand, Northern Cape Province. Just think of a counter top of this!

Thanks to Petra Enterprises' auction on eBay for the specimen and the images!

Row 9

Ellestadite

An excellent miniature of yellow ellestadite crystals in Crestmore Quarry's famous sky-blue calcite - the quarry (near Riverside in Riverside County, California) is considered by some to be the type locality for both ellestadite and fluorellestadite (ellestadite-(F). Currently, ellestadite is often a synonym for fluorellestadite or hydroxylellestadite.

Euclase

When it's clean enough, euclase (beryllium aluminum hydroxysilicate) is hard enough to be cut as a gemstone - this one, from Minas Gerais, Brazil, isn't.

Thanks to the M. Phantom Minerals table at the 2000 Carnegie Gem & Mineral Show for the specimen!

Euclase

A beautiful zoned inky-blue euclase crystal from the Mwami Mine, Karoi, Zimbabwe. The color is due to the Fe2+ - Fe3+ intervalence charge transfer that causes the absorption color band centered near 680 nm (the same phenomenon creates Prussian Blue).

Thanks to Mike Keim at Marin Minerals for the specimen and the image!

Row 10

Euclase

Another euclase from the Mwami Mine - this thumbnail's an interesting cluster of euclase with tiny white quartz.

Thanks to Brian McManus' (Pebble Peddler) auction on eBay for the specimen and the images!

Euclase
after
Beryl

This beautiful, big (5" tall and over 4 pounds) euclase after beryl comes from the Mwami Mine area (the mine closed in the early '90s).

Thanks to Brian McManus' (Pebble Peddler) auction on eBay for the specimen and the images!

Eucryptite

Eucryptite is lithium aluminum silicate - this massive miniature comes from the Foss Mica Mine on Parker Mountain, Center Strafford, New Hampshire. It's often a weathering product of spodumene.

Thanks to Greg Lesinski's (GSL Rocks) auction on eBay for the specimen!

Row 11

Eulytite
"Agricolite"

Tiny colorless to pale yellow crystals of eulytite (bismuth orthosilicate) in a vug from the Gottes Geschick Mine, Graul, Schwarzenberg District, Erzgebirge, Saxony, Germany. This is the rare monoclinic dimorph called agricolite and has an old Freiberg Mineralien-Niederlage label. I've listed this miniature here because some references consider agricolite to be merely a synonym.

Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen and the image!

Fluorellestadite

Deep-blue fluorellestadite (a calcium sulfato-phosphate silicate) crystals (larger image, center) in massive sky-blue calcite comprises most of this miniature from the type locality of the Crestmore Quarry, Riverside County, California - the yellow mineral (larger image, bottom) is probably ellestadite, a very close chemical cousin, though fluorellestadite (now named ellestadite-(F)) only forms a (complete) series with hydroxylellestadite (ellestadite-(OH)) and an (incomplete) one with the hypothetical endmember chlorellestadite (ellestadite-(Cl)). All four "ellestadites" also contain fluoride, hydorxide, and chloride cations - the predominance of which is reflected in the new Levinson-modified names.

Thanks to Vince Olsovsky's auction on eBay for the specimen!

Ellestadite-(F)

An excellent large thumbnail of darker blue fluorellestadite in lighter blue calcite, also from the Crestmore Quarry.

Thanks to Bill Kohout's auction on eBay for the specimen and the image!

Row 12

Forsterite

Forsterite's the magnesium-rich endmember of the forsterite-fayalite (iron-rich) series - it's also the "peridot" of the jewelry trade. This small cabinet specimen of drusy forsterite on pink orthoclase is from Forestport, Oneida County, New York. There's also some dark-green edenite present. Forsterite is trimorphic with ringwoodite and wadsleyite.

Thanks to Richard Koontz' auction on eBay for the specimen and the image!

Kornerupine

A nice miniature of grayish-blue kornerupine (a complex silicate) crystals in matrix from Itrongay, Madagascar. It forms an incomplete series with prismatine.

Thanks to Tony Nikischer's Excalibur Mineral Company auction on eBay for the specimen!

Kraisslite

An excellent large cabinet specimen of bronzy kraisslite (a manganese zinc magnesium iron arsenate arsenite hydroxysilicate) on matrix from the type (and only) locality of the Sterling Mine, Ogdensburg, Sussex County, New Jersey. Kraisslite is considered by some references to be in the phosphate mineral class.

Thanks to John Cianciulli's auction on eBay for the specimen and the image!

Row 13

Kyanite

This piece of kyanite (aluminum silicate) I've had forever - I don't recall where it's from. Kyanite's a trimorph with andalusite and sillimanite.

Kyanite

Most of the current good-quality kyanite comes from Minas Gerais, Brazil. This one's from Barra do Salinas.

Thanks to Rick Green at Uniquely Crystalline for the specimen and the image!

Kyanite

More kyanite from Minas Gerais, Brazil - this is a beautiful heavy spray.

Row 14

Kyanite

Sometimes kyanite can be gray or light blue - when it is, it's called "rhaetizite".

Thanks to Robert Winfree's auction on eBay for the specimen!

Kyanite

A thumbnail of the 2000 find of green kyanite with blue phantom from Minas Gerais, Brazil.

Thanks to the Carnegie Natural History Museum Store for the specimen!

Kyanite

Kyanite can be dark gray or black as in this specimen from Brazil.

Thanks to Don Clauson's auction on eBay for the specimen!

Row 15

Kyanite

A blue kyanite with a green center from a 1996 find in North Canton, Connecticut. It's true color is somewhere in between Eric's and my photographs.

Thanks to Eric Greene's (Treasure Mountain Mining) auction on eBay for the specimen and the image!

Kyanite

Occasionally kyanite gets gemmy enough to facet - this teal crystal section is from Tanzania.

Thanks to Mark Stevens' auction on eBay for the specimen!

Kyanite

A miniature of light-green kyanite from Torrington, Litchfield County, Connecticut.

Thanks to Kathy Niner's auction on eBay for the specimen!

Row 16

Kyanite, var.
Rhaetizite

Rhaetizite is also the varietal name for fibrous kyanite as in this miniature from India.

Thanks to Vince Olsovsky's auction on eBay for the specimen and the images!

Larnite

This dark-gray micro of larnite (calcium orthosilicate) comes from the Hatrurim Formation, Negev Desert, (west of the Dead Sea), Israel. It's the high-temperature, monoclinic polymorph of calcio-olivine and is a component of cement clinkers.

Thanks to the Fersman Mineralogical Institute's table at the 2006 Carnegie Gem & Mineral Show for the specimen!

Leucophoenicite

Light-purple crystals of leucophoenicite (a manganese hydroxysilicate) line a pocket in this thumbnail from the type locality of Franklin, Sussex County, New Jersey. It has a Brandywine Minerals tag.

Thanks to Dru Wilbur's auction on eBay for the specimen!

Row 17

Leucophoenicite

An excellent miniature of deep-pink leucophoenicite in a typical franklinite ore matrix, again from the type locality.

Thanks to Tony Nikischer's Excalibur Mineral Company auction on eBay for the specimen and the image!

Magnesiostaurolite

An excellent micro of yellowish magnesiostaurolite (a complex aluminum magnesium silicate) from the Varaita Valley, Dora Maira Massif, Cuneo Province, Piedmont, Italy. It often includes traces of iron, lithium, titanium, and zinc.

Thanks to Paolo Bracci's auction on eBay for the specimen and the image!

Malayaite

When tin replaces the titanium in titanite, it becomes malayaite. The malayaite in this small thumbnail from Ash Mountain, McDame, British Columbia, Canada occurs as millimeter-sized green acicular tufts. Malayaite also forms an incomplete series with vanadomalayaite, its vanadium analog.

Thanks to Doug Miller at Northern Lights Minerals for the specimen!

Row 18

Mcgovernite

An attractive small cabinet specimen of deep-brown mcgovernite (a manganese zinc magnesium arsenatohydroxysilicate) plates (larger image, top row center and bottom row left) on a willemite, franklinite, and calcite matrix from the type locality of the Sterling Mine, Ogdensburg, Franklin Mining District, Sussex County, New Jersey. There are at least three different formulas for mcgovernite.

Thanks to Carl Bentley's auction on eBay for the specimen and the images!

Merwinite

Merwinite's a fairly rare calcium magnesium silicate - this bluish-gray one with calcite comes from the type locality of the Crestmore Quarry, Riverside, California. It's named after Herbert E. Merwin, the American geophysicist.

Thanks to Nature's Expressions' table at the Carnegie Gem & Mineral Show for the specimen!

Monticellite

Monticellite's about as generic a silicate as you can get, CaMgSiO4 (and forms a series with kirschteinite where iron replaces the magnesium) - here it occurs as gray grains in a blue calcite matrix from the Crestmore Quarry in Riverside County, California.

Thanks to Don Goodell's auction on eBay for the specimen!

Row 19

Mozartite

A micro of dark-red mozartite (a manganese calcium hydroxysilicate) crystals on matrix from the type locality of the Cerchiara Mine, Borghetto Vara, La Spezia Prov, Liguria, Italy.

Thanks to Paolo Bracci's auction on eBay for the specimen and the image!

Mullite

An excellent micro of fine acicular white and lilac mullite (aluminum silicate) on matrix from Nickernich, Sattel, Eifel Mountains, Germany. Long known as a synthetic refractory produced during clay firings, its composition varies widely - mullites with an alumina:silica ratio greater than 3:2 have the highest melting point (1810° C). Mullite needles are found in porcelain and the mullite refractory business today is a large one, encompassing dozens of companies.

Thanks to Martin Gale's auction on eBay for the specimen!

Mullite

From the Ettringer Bellerberg Mt, also in the Eifel Mountains, comes this beautiful lavender tuft of mullite on a miniature matrix.

Thanks to Sönke Stolze's Systematic-Minerals.com auction on eBay for the specimen and the images!

Row 20

Norbergite

An excellent miniature of brown norbergite (a magnesium hydroxyfluorosilicate) in matrix from somewhere in Canada. It's a member of the humite group and subgroup.

Thanks to Vince Olsovsky's auction on eBay for the specimen and the images!

Norbergite

This interesting small-cabinet specimen comprises orange norbergite and black graphite in Franklin marble from the Limecrest Quarry, Sparta Township, Sussex County, New Jersey.

Thanks to John Landmesser's auction on eBay for the specimen and the image!

Ottrélite

A nice thumbnail of tiny dark-green ottrélite rosettes (larger image, bottom row) in matrix from the type locality of Ottré, Stavelot Massif, Luxembourg Province, Belgium. Ottrélite is a manganese iron magnesium aluminohydroxysilicate and forms two series; one with chloritoid where iron predominates and another series with magnesiochloritoid where magnesium is prevalent.

Thanks to Adam Larson's Adam's Minerals auction on eBay for the specimen and the image!

Row 21

Paraspurrite

Paraspurrite often occurs as powdery coatings on matrix as in this small cabinet piece from the type locality of the Darwin Mines, Darwin, Inyo County, California. It's a calcium carbonatosilicate and is a dimorph of spurrite.

Thanks to SoCal Nevada's auction on eBay for the specimen and images!

Phenakite

A beautiful pair of phenakites (beryllium silicate) from the famous Mt. Antero, Chaffee County, Colorado locale - when transparent they're sometimes used as gemstones.

Thanks to Greg Holland at the Stone Haven Mineral Shoppe for the specimen and the image!

Poldervaartite

A beautiful thumbnail of a poldervaartite (a calcium manganese hydroxysilicate) crystal aggregate on matrix from the N'Chwaning I Mine, Kuruman, South Africa. Poldervaartite is the calcium-dominant analog of the recently (2007) discovered manganese-dominant olmiite.

Thanks to John Veevaert at Trinity Minerals for the specimen and the images!

Row 22

Poldervaartite

It's hard to belive that this specimen and the previous one are the same mineral! Poldervaartite runs the gamut from colorless transparent rhombs like this through cream-colored translucent "wheat sheafs" through tan prisms to raspberry-red aggregates.

Thanks to Debbie Woolf at Steiner's Rockshop for the specimen and images!

Poldervaartite

Here's a third habit and color of poldervaartite - this miniature's also from the N'Chwaning I Mine. The poldervaartite-producing part of the mine emptied out rather quickly, so it's unlikely that there'll be many more of these. The "wheat sheafs" on this specimen (larger image, bottom center) may be the manganese-dominant olmiite.

Thanks to Debbie Woolf at Steiner's Rockshop for the specimen and images!

Poldervaartite &
Bultfonteinite

A beautiful thumbnail of a fourth habit of poldervaartite - tan cleanly-terminated prisms, cushioned by white sprays of bultfonteinite on matrix from the 2004 find at the N'Chwaning II Mine, Kalahari manganese fields, Northern Cape Province, South Africa.

Thanks to Rocko Minerals' auction on eBay for the specimen!

Row 23

Poldervaartite &
Bultfonteinite

This miniature of poldervaartite and bultfonteinite is also from that 2004 find - the poldervaartite is more dispersed and the bultfonteinite is less disseminated.

Thanks to Kerry Day's (Kaygeedee Minerals) auction on eBay for the specimen!

Prismatine

A nice thumbnail of translucent brown prismatine (the boron analog of kornerupine) in an enstatite/muscovite matrix from the first known location in Sweden, the Stakholmen Quartz Quarry, Hassela, Hälsingland, Sweden. It forms an incomplete series with kornerupine.

Thanks to Göran Axelsson's auction on eBay for the specimen and the image!

Reinhardbraunsite

An excellent micro of pink reinhardbraunsite (a calcium fluorohydroxysilicate) from the type locality of Bellerberg, Ettringen, Eifel Mountains, Germany. The photo was taken at 20X. It has an M&W Minerals (Milford, MI) tag. Reinhardbraunsite is the natural equivalent of synthetic calciochondrodite.

Thanks to Chris Stefano's auction on eBay for the specimen and the image!

Row 24

Rondorfite

An excellent micro of reddish-brown rondorfite (a calcium magnesium silicate-chloride with traces of iron, aluminum, sodium, and titanium) in matrix from the type locality of the Caspar quarry near the Bellerberg volcano, Ettringen, Mayen, Eifel, Rhineland-Palatinate, Germany. A recent study (2011) has shown that rondorfite also includes a hydroxy cation and water of hydration.

Thanks to Lester Burgess' auction on eBay for the specimen!

Sillimanite

A large cabinet specimen of compacted fibrous and somewhat chatoyant sillimanite (aluminum silicate and the polymorph of andalusite and kyanite) from an odd occurrence at Brandywine Springs, Red Clay Creek Valley near Wilmington, New Castle County, Delaware. The sillimanite here occurs as boulders in and along the streambed.

Thanks to Keith Robertson's auction on eBay for the specimen and the images!

Sillimanite

An excellent pale blue 9.7mm rare sillimanite crystal from Mogok, Sagaing District, Mandalay Division, Burma (Myanmar). Sillimanite occurs in a range of pastel colors - this one is a rare 2.95 ct 9.8mm x 7.4mm x 5.6mm oval. Catseye sillimanite is called "fibrolite" in the jewelry trade.

Thanks to Darlene Cobler's auction on eBay for the specimen and the images!

Row 25

Sonolite

An old miniature of dark-brown sonolite (a manganese fluorohydroxysilicate) and pink rhodonite in manganese ore matrix from the Rito Mine, Gunma Prefecture, Kanto Region, Honshu Island, Japan. Ex: Joe Cilen Collection.

Thanks to Tony Nikischer's Excalibur Mineral Company auction on eBay for the specimen!

Spurrite

A nice reference cabinet piece of spurrite (the calcium carbonatosilicate dimorph of paraspurrite) with probable paraspurrite on the back (larger image, right) from the Fuka Mine, Bitchu-Cho, Okayama Prefecture, Chugoku Region, Honshu Island, Japan. It's sometimes cabbed for jewelry.

Thanks to Gloria's Minerals' table at the Carnegie Gem & Mineral Show for the specimen!

Staurolite

Staurolite (a complex iron magnesium lithium aluminosilicate) almost always forms interpenetration twins, mostly 60° and rarely 90° - this small cabinet piece of "fairy crosses" in muscovite schist is from Keivy, Kola Peninsula, Russia. Some analyses show zinc present as well.

Thanks to Cathy Krismanits' (Southwestern Sales) auction on eBay for the specimen!

Row 26

Staurolite

A single staurolite crystal thumbnail from Minas Gerais, Brazil.

Thanks to Mike Keim at Marin Minerals for the specimen and the image!

Tadzhikite-(Y)
in
Sogdianite

Brown crystals of tadzhikite-(Y) (a complex rare-earth borosilicate) in pink sogdianite (a complex cyclosilicate) from the type locality (for both) of the Dara-i-Pioz Glacier, Tien Shan Mountains, Tajikistan. It forms a complete series with tadzhikite-(Ce) where cerium predominates over yttrium and an incomplete series with hellandite-(Y). Some references claim that tadzhikite-(Y) exists only as tadzhikite-(Ce). It has a Fersman Mineralogical Museum tag.

Thanks to Graeber & Himes' table at the 2004 Carnegie Gem & Mineral Show for the specimen!

Tephroite

A small cabinet specimen of massive gray tephroite (manganese orthosilicate) with translucent red zincite from the type locality of the Franklin Mine, Franklin, Sussex County, New Jersey. It forms a series with fayalite, its iron analog.

Thanks to John Cianciulli's auction on eBay for the specimen!

Row 27

Thaumasite

A 7.25mm gemmy thaumasite (a hydrated calcium complex silicate) crystal collected in 1987 from the N'Chwaning II Mine, Kalahari manganese fields, Northern Cape Province, South Africa.

Thanks to Rick Kennedy's auction on eBay for the specimen!

Titanite

Gemmy green titanite (or sphene) crystals with red zoning from Turmic Gillit, Northern Argas, Pakistan. Titanite's (calcium titanium silicate) almost hard enough to be a gemstone - the colors and dispersion are magnificent!

Thanks to Rocko's auction on eBay for the specimen!

Titanite

Another one that was hard to categorize - yellowish-green titanite, light-green epidote, and black magnetite on matrix from California - the triangular striations on the magnetite are wonderful!

Thanks to Frank P. Butler's auction on eBay for the specimen and images!

Row 28

Titanite

Sharp transparent brown titanites from the Poudrette Quarry, Mont St. Hilaire, Quebec, Canada.

Thanks to Tim Jokela, Jr. at Element 51 for the specimen!

Titanite

A beautiful "chrome sphene" crystal from San Quentin, Ensenada, Baja California Norte, Mexico. Ex F. Marshall collection, originally purchased from Pala Properties International in 1972.

Thanks to Sharon Cisneros at the Mineralogical Research Company for the specimen!

Titanite

An equally pretty light green titanite (no chromium in this one) from probably the Fazenda Rubin Pimenta Mine, Capelinha, Minas Gerais, Brazil.

Thanks to Sharon Burnett's auction on eBay for the specimen and the image!

Row 29

Titanite

Parallel crystals of glossy black titanite comprise this miniature from the Cardiff Uranium Mine, Wilberforce, Monmouth Township, Haliburton County, Ontario, Canada.

Thanks to Marvin Schwalb's auction on eBay for the specimen!

Titanite

A micro with a tiny but bright orange titanite crystal on matrix from Mendig, Lacher See, Eifel Mountains, Germany.

Thanks to Martin Gale's auction on eBay for the specimen and the image!

Vuagnatite

Colorless gemmy millimeter-sized crystals of vuagnatite (a calcium aluminum hydroxysilicate) share this small cabinet specimen with blue and green mcguinnessite from the Copper King Prospect, Red Mountain, Mendocino County, California. Vuagnatite forms an incomplete series with mozartite where manganese replaces some of the aluminum. Ex: J. F. Cooper Collection.

Thanks to Mike Keim at Marin Minerals for the specimen and the images!

Row 30

Wadalite

Light-yellow rough crystals of wadalite (a calcium aluminum iron magnesium silicate-chloride) on matrix comprise this micro from the Caspar quarry near the Bellerberg volcano, Ettringen, Mayen, Eifel, Rhineland-Palatinate, Germany. It's isostructural with the garnet group and has recently (2009) been found in certain types of meteorites.

Thanks to Kristen Burgess' auction on eBay for the specimen!

   

maintained by: Alan Guisewite

Last Update 23 Jun 2013