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| Stibiotantalite is
named from its Antimony (Sb) content (the Greek word for Antimony
is stibio) and its relation
to Tantalite.
| Discovered
in 1893;
IMA
status: Valid (pre-IMA; Grandfathered) |
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Chemistry
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Chemical
Formula: |
Sb(Ta,Nb)O4
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Antimony
Tantalum Oxide |
Molecular
Weight: |
366.70 gm
|
Composition: |
Tantalum |
49.35 % |
Ta |
60.25 % |
Ta2O5 |
|
Antimony |
33.20 % |
Sb |
41.93 % |
SbO2 |
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Oxygen |
17.45 % |
O |
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|
|
100.00 % |
|
102.18 % |
= TOTAL OXIDE |
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Classification
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Mineral
Classification: |
Oxides
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Strunz 8th
Ed. ID:
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4/D.25-30
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Nickel-Strunz 10th
Ed. ID:
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4.DE.30
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4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
D : Metal: Oxygen = 1:2 and similar E : With medium-sized cations; with various polyhedra
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Related
to: |
Cervantite Group.
Stibiocolumbite - Stibiotantalite Series.
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Members
of Group: |
Cervantite Group:
Bismutocolumbite, Bismutotantalite, Cervantite, Clinocervantite,
Stibiocolumbite, Stibiotantalite
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Varieties: |
Bismuthian Stibiotantalite
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Synonyms: |
None
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Crystal
Data
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Crystallography:
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Orthorhombic
- Pyramidal |
Crystal
Habit:
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Crystals
prismatic || [010], flattened || to [001],
may be equant, to 12 cm; {001} and {101} striated || [010].
|
Twinning:
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About
[010] with composition plane {001}; polysynthetic.
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Physical
Properties
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Cleavage: |
Distinct
on {001}, Indistinct on {100}
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Fracture: |
Sub-Conchoidal
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Tenacity:
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Brittle
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Moh's
Hardness: |
5.5
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Density:
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5.98
- 7.53 (g/cm3)
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Luminescence:
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None
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Radioactivity:
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Not
Radioactive |
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Optical
Properties
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Color: |
Yellow, greenish yellow, yellowish brown,
reddish brown, brown |
Transparency: |
Transparent
to Translucent |
Luster: |
Adamantine
to Resinous |
Refractive
Index: |
2.374
- 2.457 Biaxial ( + ) |
Birefringence: |
0.0826
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Dispersion: |
0.146;
Relatively Strong; r < v |
Pleochroism: |
Colorless
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Occurances
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Geological
Setting: |
An
uncommon accessory mineral in complex granite pegmatites.
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Common
Associations: |
Tantalite
(Greenbushes, Western Australia); Antimony, Allemontite,
Microlite, Stibiomicrolite, Lithiophilite, alkalic Beryl,
Cassiterite, Columbite–Tantalite (Varuträsk, Sweden).
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Common
Impurities: |
Nb
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Type
Locality: |
Greenbushes Sn placers, Greenbushes Tinfield, Western Australia, Australia
|
Year
Discovered: |
1893
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View
mineral photos: |
Stibiotantalite
Mineral Photos and Locations |
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More
Information
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|
Mindat.org
Webmineral.com
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Stibiotantalite
is extremely rare as a faceted gem. Stibiotantalite
crystals are fairly rare and usually almost opague or
very heavily included, so transparent gems are extremely rare. Stibiotantalite is strongly birefringent which may
give gems with any clarity a sleepy look due to doubling
of the back facets when seen through the table. Clean, facetable crystals are extremely
rare.
These
locations may be th only sources of facetable crystals:
Rio Grande do Norte,
Brazil; Alto
Ligonha District, Zambezia Province, Mozambique; and in the USA at San Diego County,
California.
Distribution:
From the Greenbushes tin placers, Wodgina district,
Western Australia. Large crystals at the Muiâne and
other mines, Alto Ligonha, Mozambique. From the Benson
mine, Mtoko, Zimbabwe. In the USA, from Topsham, Sagadahoc
County, Maine; in California, in San Diego County, fine
crystals from the Himalaya mine, Mesa Grande district;
at the Katerina, Stewart, and Vandenburg mines, Pala
district; and in the Little Three mine, Ramona district;
in the Brown Derby pegmatite, Gunnison County, Colorado.
In the Varuträsk pegmatite, 15 km northwest of Skellefteå,
Västerbotten, Sweden. From the Voronya massif, Kola
Peninsula, Russia. Found near Stak Nala, Gilgit district,
Pakistan.
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Stibiotantalite
gems for sale:
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Gem:
|
Stibiotantalite |
Stock
#:
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STIBIO-002 |
Weight:
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0.1560
ct |
Size: |
2.58
x 1.53 mm |
Shape: |
Round |
Color: |
Straw Yellow |
Clarity: |
SI2 |
Origin: |
Rio
Grande do Norte, Brazil |
Treatment: |
None
(natural) |
Price: |
SOLD
(but we have others) |
Pictures
are of the actual gem offered for
sale. Gem images are magnified to
show detail. |
|
|
An
extremely rare gem from
Alto do Giz pegmatite, Equador, Seridó Oriental, Rio Grande do
Norte, Northeast Region, Brazil that
is eye clean with ideal color.
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|
Gem:
|
Stibiotantalite |
Stock
#:
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STIBIO-001 |
Weight:
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0.1860
ct |
Size: |
4.11
x 3.22 x 1.51 mm |
Shape: |
Fancy
Triangle |
Color: |
Straw Yellow |
Clarity: |
Eye
Clean |
Origin: |
Rio
Grande do Norte, Brazil |
Treatment: |
None
(natural) |
Price: |
SOLD
(but we have others) |
Pictures
are of the actual gem offered for
sale. Gem images are magnified to
show detail. |
|
|
An
extremely rare gem from
Alto do Giz pegmatite, Equador, Seridó Oriental, Rio Grande do
Norte, Northeast Region, Brazil that
is eye clean with ideal color.
|
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