| 13 Rows |
|---|
 Boracite
A 3mm boracite (a magnesium chloroborate) crystal on matrix from Bernburg, Saxony, Germany. Boracite's one of the hardest borates (7 - 7.5) and is also pyro and piezoelectric - it forms a complete series with ericaite, its iron analog and is dimorphic with trembathite. Manganese (chambersite) can partially replace the magnesium. Synthetic boracites are studied for sensor and actuator applications - the nickel and chromium boracties are also ferroelectric. Thanks to Mike Keim at Marin Minerals for the specimen! |
|
 Boracite
Two intergrown boracite cubes from Sehnde, Hanover, Germany. Thanks to Robert Stoufer's auction on eBay for the specimen and the image! |
|
 Boracite
A deep grayish-green boracite crystal from Solveigh Hall (Solvayhall), Bernberg, Germany. It's unfortunate that boracite crystals are invariably so small! Ex: James Carryer Collection Thanks to the Shadyside Mining Company table at the 2003 Carnegie Gem & Mineral Show for the specimen! |
|
| Row 2 |
|---|
 Boracite
This 1cm pale blue-green boracite crystal is from the Alto Chapare district, Chapare Province, Cochabamba Department, Bolivia, and was collected by Alfredo Petrov, the Bolivian mineral dealer. Thanks to Jan Garland's (Fine Rocks) auction on eBay for the specimen and the images! |
|
 Boracite
A very sharp blue-green 3mm boracite crystal with octahedral corner mods from the Gröne Mine, Bernburg, Germany. Thanks to Peter Maurer's auction on eBay for the specimen and the image! | |
|
 Canavesite
Canavesite's a very rare magnesium carbonatohydroborate that usually occurs as beautiful tiny acicular radiating clusters, as in this miniature from the type locality of the Miniera Salvere, Brosso (pyrite) Mine, Ivrea, Italy. The matrix is a magnetite-pyrite mix. Thanks to Brian McManus' (Pebble Peddler) auction on eBay for the specimen! | | |
|
| Row 3 |
|---|
 Colemanite
This colemanite (a calcium hydroxyborate) comes from the Boron Pit, U.S> Borax Mine, Boron, Kern County, California. It's mined as an ore of boron and used in making borax. Thanks to Tom & Vicki Loomis at Dakota Matrix Minerals for the specimen! |
|
 Colemanite
A beautiful sharp thumbnail colemanite crystal from the type locality of the Furnace Creek District, Death Valley, Inyo County, California. Collected in the 1950s, it fluoresces light orange under longwave UV. Thanks to Frank Butler's auction on eBay for the specimen and the image! | | |
|
 Fluoborite
A miniature of compacted fibrous fluoborite (magnesium hydroxyfluoborate) from the New Method Mine, Bristol Mountains, Amboy, Mojave Desert, Near Ludlow, San Bernadino County, California. Thanks to Anthony Jones' auction on eBay for the specimen! |
|
| Row 4 |
|---|
 Gaudefroyite
Gaudefroyite's a calcium manganese hydroxycarbonatoborate. This was a difficult specimen to photograph - the needles are gaudefroyite and there's a few hematites (larger image, closeup) and the grayer area has a coating of hausmannite (a manganese oxide, here probably a weathering product). This one came from the Kalahari manganese fields, Kuruman, South Africa. Thanks to Chris Korpi at Pangaea Minerals for the specimen! |
|
 Gaudefroyite
Excellent crystals of gaudefroyite on quartz with yellow crystalline and granular ettringite and a thin layer of andradites from one of the N'Chwaning Mines in the Kalahari manganese fields, Kuruman, South Africa. Thanks to Veronica Matthews' auction on eBay for the specimen! |
|
|
| Row 5 |
|---|
 Hambergite
A rare thumbnail of hambergite (beryllium hydroxymetaborate) from the Himalaya Mine, Mesa Grande, San Diego County, California. It's another one of the hard (7.5) borates. Thanks to Mike Keim at Marin Minerals for the specimen and the image! |
|
 Henmilite
Crystals of deep blue henmilite (calcium copper hydroxyborate) on a calcite (miniature) matrix from the 2003 find at the type (and only) locality of the Fuka Mine, Bitchu-Cho Okayama Prefecture, Japan Thanks to John Veevaert at Trinity Minerals for the specimen and the images! | |
|
 Henmilite
A single 5mm henmilite crystal from the same occurrence at the Fuka Mine, Japan. Thanks to Val Collins' auction on eBay for the specimen and the image! | |
|
| Row 6 |
|---|
 Hydroboracite
A miniature of hydroboracite (a hydrated calcium magnesium borate) on anhydrite from the anhydrite mine at Niedersachswerfen, Nordhausen, Harz Mts, Thuringia, Germany. Collected by Emil Stoyanov. Thanks to Emil Stoyanov's auction on eBay for the specimen and the images! |
|
 Inderite
Two thumbnails of inderite (magnesium hydroxyborate pentahydrate and the dimorph of kurnakovite) from Boron, Kern County, California. Thanks to Mike Keim at Marin Minerals for the specimen and the image! |
|
 Jeremejevite
Jeremejevite's a hard borate (7) and it often occurs in pale blue facetable crystals like this one from the North End of Erongo Massif,
Namibia. It's an aluminum hydroxyfluoroborate. Thanks to SoCal Nevada's auction on eBay for the specimen and images! |
|
| Row 7 |
|---|
 Kurnakovite
A miniature of transparent kurnakovite (magnesium hydroxyborate pentahydrate) from (maybe the Baker Mine operation at) the U.S. Borax Mine, Boron, Kern County, California, and collected by Jack Crawford, geologist for U.S. Borax. It's dimorphic with inderite. |
|
 Londonite
Londonite's a rare cesium potassium beryllium aluminum berylloborate, that generally occurs in small dodecahedral crystals, like this 4mm one from the type locality of the Antandrokomby pegmatite, Mt.Ibity, Antsirabe, Antananarivo Province, Madagascar. It forms a series with rhodizite, where the potassium predominates. Thanks to Martin Gale's auction on eBay for the specimen and the image! | |
|
 Ludwigite
A miniature of dark green ludwigite (a magnesium iron borate) intergrown with chalcopyrite from the Brosso Mine, Level 365, Piedmont, Italy. Ex: Bachman Collection. Thanks to Steve & Susan Bringe's (Summit Minerals) auction on eBay for the specimen and the image! |
|
| Row 8 |
|---|
 Meyerhofferite
A nice reference specimen of meyerhofferite (a calcium hydroxyborate) from Death Valley, Inyo County, California (may be from the type locality of the Mount Bianco Mine). Ex: Twin Seas Estate. Thanks to Jeff & Heather McCammon's (Second Nature Colorado) auction on eBay for the specimen and the images! |
|
 Pinakiolite
A miniature of glossy black tabular pinakiolite (a magnesium manganese antimony pentaborate) crystals in dolomite from the type locality of Långban, Filipstad, Värmland, Sweden. It's a polymorph with fredrikssonite, orthopinakiolite, and takéuchiite. Thanks to Tony Jones' auction on eBay for the specimen! | |
|
 Pinnoite
This miniature of crystalline pinnoite (a hydrated magnesium borate) on a borate (probably inderite) matrix is from the Inder B deposit and salt dome, Atyrau, Kazakhstan. Thanks to Adam Larson's (Adam's Minerals) auction on eBay for the specimen! |
|
| Row 9 |
|---|
 Priceite
A miniature of massive priceite (a hydrated calcium borate) from Mule Canyon, Yermo, San Bernardino County, California. This piece is from the Harry Uhl Collection and was collected August 12, 1940. Thanks to Jennings "Beau" Gordon's (Jendon Minerals) auction on eBay for the specimen! |
|
 Probertite
A miniature of rare probertite (a hydrated sodium calcium hydroxyborate) crystals from the 1987 find at the Borax Open Pit, Boron, Kern County, California (the finest U.S. occurrence ever reported). Thanks to Tony Nikischer at the Excalibur Mineral Company for the specimen! |
|
 Rhodizite
The hardest (8 - 8.5) borate is rhodizite, a rare potassium cesium beryllium aluminum berylloborate, that generally occurs in small dodecahedral crystals, like this one from west of Sahanivotry, Sahatany Valley, about 50 km south of Antsirabe, Tsilaisina, Madagascar. It forms a series with londonite, where the cesium predominates (over the potassium) - though no pure potassic end member has been found. Thanks to Emilie & Ron Kendig's auction on eBay for the specimen! |
|
| Row 10 |
|---|
 Rhodizite
A small miniature of rhodizite on feldspar from Mt. Bity, Antandrokomby, Madagascar. There's also a purplish-red unidentified crystal (larger image, lower right) present. Thanks to Anthony Jones' auction on eBay for the specimen! |
|
 Rhodizite
A colorful miniature from Madagascar comprising a yellow rhodizite, red elbaites, and a blue beryl. Thanks to Mike Keim at Marin Minerals for the specimen and the images! | |
|
 Sassolite
Near type locality sassolite (natural boric acid) on gypsum miniature from Larderello, Pomarance, Cecina valley, Pisa, Tuscany, Italy. Thanks to Kim & Cindy Strange's auction on eBay for the specimen and the image! |
|
| Row 11 |
|---|
 Szaibelyite
A nice miniature cluster of szaibelyite (magnesium hydroxyborate) fibers from Dypingdal, Snarum, Buskerud, Norway. It forms a series with sussexite where manganese partially replaces the magnesium. Thanks to Anthony Jones' auction on eBay for the specimen! |
|
 Szaibelyite,
var. Ascharite
Off-white coatings of the ascharite variety of szaibelyite on magnetite with minor pyrite and serpentine from the Brosso Mine, Torino, Italy. At one time, ascharite was considered a separate mineral - some references now them to be synonymous. Thanks to Kim & Cindy Strange's auction on eBay for the specimen! |
|
 Teepleite
A thumbnail of massive teepleite (a sodium hydroxyborate chloride) from Borax&nbp;Lake, Lake County, California. Ex: Joe Cilen Collection with an early Frazier's label. Thanks to David H. Garske's (MINERALS and MORE) auction on eBay for the specimen! |
|
| Row 12 |
|---|
|
|
 Tincalconite
This tincalconite (hydrated sodium borate) thumbnail comes from California. It's often a dehydration product of borax - I can't tell whether that's the case here. |
|
|
| Row 13 |
|---|
 Ulexite
The famous "TV rock", this sodium calcium borate presaged the fiber optic industry. This habit only occurs in Boron, Kern County, California. |
|
 Ulexite
Ulexite more often occurs as random needles and tufts - as in this second specimen from Boron, California. The white chunky crystals are probably borax. Thanks to Jean & Audrey's (ALKO) auction on eBay for the specimen! |
|
 Veatchite on
Colemanite
A very nice (and very fragile) miniature of veatchite crystals on colemanite from the Billie Mine, Furnace Creek district, Death Valley, Inyo County, California. Thanks to Tony Jones' auction on eBay for the specimen! |
|
