From Surf Wiki (app.surf) — the open knowledge base

Tetrahedrite

Copper antimony sulfosalt mineral

Field	Value
name	Tetrahedrite
category	Sulfosalt mineral
image	Tetrahedrite - Black Pine mine, Granite Co., Montana, USA.jpg
imagesize	260px
caption	Tetrahedrite crystal with traces of quartz (in middle) and micro mimetite, specimen size 3.5 × 2.5 × 2.5 cm
formula
strunz	2.GB.05
system	Cubic
class	Hextetrahedral (3m)
H-M symbol: ( 3m)
symmetry	I3m
unit cell	a = 10.39(16) Å; Z = 2
color	Steel gray to iron-gray
habit	Groups of tetrahedral crystals; massive, coarse to fine compact granular
twinning	Contact and penetration twins on {111}
cleavage	None
fracture	Uneven to subconchoidal
tenacity	Somewhat brittle
mohs	4
luster	Metallic, commonly splendent
streak	Black, brown to dark red
refractive	n greater than 2.72
opticalprop	Isotropic
gravity	4.97
diaphaneity	Opaque, except in very thin fragments
references

H-M symbol: ( 3m) Tetrahedrite is a copper antimony sulfosalt mineral with the formula: . It is the antimony endmember of the continuous solid solution series with arsenic-bearing tennantite. Pure endmembers of the series are rarely if ever seen in nature. Of the two, the antimony rich phase is more common. Other elements also substitute in the structure, most notably iron and zinc, along with less common silver, mercury and lead. Bismuth also substitutes for the antimony site and bismuthian tetrahedrite or annivite is a recognized variety. The related, silver dominant, mineral species freibergite, although rare, is notable in that it can contain up to 18% silver.

Mineralogy

Tetrahedrite gets its name from the distinctive tetrahedron shaped cubic crystals. The mineral usually occurs in massive form, it is a steel gray to black metallic mineral with Mohs hardness of 3.5 to 4 and specific gravity of 4.6 to 5.2.

Tetrahedrite occurs in low to moderate temperature hydrothermal veins and in some contact metamorphic deposits. It is a minor ore of copper and associated metals. It was first described in 1845 for occurrences in Freiberg, Saxony, Germany. Historically, it was an important ore of copper, the formula CuSbS corresponding with 57.5% of the metal; it was also worked as an ore of silver, of which element it sometimes contains as much as 30%.

Applications

The now-defunct company Alphabet Energy announced plans to offer a thermoelectric device based on tetrahedrite to turn heat into electricity. The company claimed that other thermoelectrics typically produce about 2.5 percent efficiency, while tetrahedrite could achieve 5 to 10 percent.

Other thermoelectrics are either scarce, expensive ($24–146/kg vs $4 for tetrahedrite) and/or toxic. Working with a natural material also reduces manufacturing costs.

Images

File:Tetrahedrite-Chalcopyrite-Sphalerite-251531.jpg|Tetrahedrite crystals with chalcopyrite and sphalerite from the Casapalca Mine, Peru (size: 8.2 × 6.4 × 4.7 cm) File:Tetrahedrite-27120.jpg|Tetrahedrite from Casapalca Mine, Casapalca, Huarochiri Province, Lima Department, Peru File:Fluorite-Quartz-Rhodochrosite-ed10a.jpg|Rhodochrosite with fluorite, tetrahedrite and quartz; the tetrahedrite occurs as sharp, metallic crystals File:Quartz-Tetrahedrite-denv08-50b.jpg|Tetrahedrite crystals to several inches on size in combination with quartz crystals

References

"Handbook of Mineralogy".
(2014-07-12). "Tetrahedrite: Tetrahedrite mineral information and data". Mindat.org.
{{EB1911. Leonard James. Spencer
Jacobs, Suzanne. (2014-07-12). "Cheaper Thermoelectric Materials | MIT Technology Review". Technologyreview.com.

Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

copper-ores iron-minerals sulfosalt-minerals antimony-minerals cubic-minerals minerals-in-space-group-217 thermoelectricity

Want to explore this topic further?

Ask Mako anything about Tetrahedrite — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report