Pearceite-T2ac
A structural variant of Pearceite
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About Pearceite-T2ac
Formula:
[Ag6As2S7][Ag9CuS4]
Colour:
Black
Lustre:
Metallic
Hardness:
2 - 3
Specific Gravity:
6.18 - 6.23
Crystal System:
Trigonal
Name:
For Richard Pearce (1837-1927), US chemist
First Recorded Locality:
A polytype of Pearceite
Pearceite-Polybasite series
The old species "arsenpolybasite" is now classified as the polytypes Pearceite-T2ac or Pearceite-M2a2b2c (redefinition; see Bindi et al., 2007).
Pearceite-Polybasite series
The old species "arsenpolybasite" is now classified as the polytypes Pearceite-T2ac or Pearceite-M2a2b2c (redefinition; see Bindi et al., 2007).
Unique Identifiers
Mindat ID:
367
Long-form identifier:
mindat:1:1:367:8
Classification of Pearceite-T2ac
5.2.6
5 : Sulphosalts - Sulpharsenites and Sulphobismuthites (those containing Sn, Ge,or V are in Section 6)
2 : Sulpharsenites etc. of Ag
5 : Sulphosalts - Sulpharsenites and Sulphobismuthites (those containing Sn, Ge,or V are in Section 6)
2 : Sulpharsenites etc. of Ag
Physical Properties of Pearceite-T2ac
Metallic
Transparency:
Opaque
Colour:
Black
Comment:
Dark red in transmitted light
Hardness:
2 - 3 on Mohs scale
Tenacity:
Brittle
Cleavage:
Imperfect/Fair
Imperfect od {001}
Imperfect od {001}
Fracture:
Irregular/Uneven
Density:
6.18 - 6.23 g/cm3 (Measured)
Chemistry of Pearceite-T2ac
Mindat Formula:
[Ag6As2S7][Ag9CuS4]
Element Weights:
Elements listed:
Common Impurities:
Fe
Crystallography of Pearceite-T2ac
Crystal System:
Trigonal
Class (H-M):
3 2 - Trapezohedral
Space Group:
P3 2 1
Cell Parameters:
a = 14.9746(17) Å, c = 11.9982(6) Å
Ratio:
a:c = 1 : 0.801
Unit Cell V:
2,330.01 ų (Calculated from Unit Cell)
Z:
4
Comment:
Data from Bindi et al. (2007).
First Recorded Occurrence of Pearceite-T2ac
Synonyms of Pearceite-T2ac
Other Language Names for Pearceite-T2ac
Common Associates
Associated Minerals Based on Photo Data:
| 7 photos of Pearceite-T2ac associated with Proustite | Ag3AsS3 |
| 6 photos of Pearceite-T2ac associated with Calcite | CaCO3 |
| 4 photos of Pearceite-T2ac associated with Pyrite | FeS2 |
| 4 photos of Pearceite-T2ac associated with Chalcopyrite | CuFeS2 |
| 4 photos of Pearceite-T2ac associated with Stilbite Subgroup | M6-7[Al8-9Si27-28O72] · nH2O |
| 3 photos of Pearceite-T2ac associated with Acanthite | Ag2S |
| 3 photos of Pearceite-T2ac associated with Rammelsbergite | NiAs2 |
| 3 photos of Pearceite-T2ac associated with Nickelskutterudite | NiAs3 |
| 3 photos of Pearceite-T2ac associated with Rhodochrosite | MnCO3 |
| 2 photos of Pearceite-T2ac associated with Native Silver | Ag |
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Pearceite-T2ac
mindat.org URL:
https://www.mindat.org/min-367.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
References for Pearceite-T2ac
Reference List:
Frondel, Clifford (1963) Isodimorphism and the polybasite and pearceite series. American Mineralogist, 48 (5-6) 565-572
IMA (1967) International Mineralogical Association: Commission on New Minerals and Mineral Names. Mineralogical Magazine and Journal of the Mineralogical Society, 36 (277) 131-136 doi:10.1180/minmag.1967.036.277.20
Bindi, Luca, Evain, Michel, Menchetti, Silvio (2006) Temperature dependence of the silver distribution in the crystal structure of natural pearceite, (Ag,Cu)16(As,Sb)2S11. Acta Crystallographica Section B Structural Science, 62 (2) 212-219 doi:10.1107/s010876810600108x
Evain, Michel, Bindi, Luca, Menchetti, Silvio (2006) Structural complexity in minerals: twinning, polytypism and disorder in the crystal structure of polybasite, (Ag,Cu)16(Sb,As)2S11. Acta Crystallographica Section B Structural Science, 62 (3) 447-456 doi:10.1107/s010876810600975x
Localities for Pearceite-T2ac
symbol to view information about a locality.
The Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
All localities listed without proper references should be considered as questionable.
China | |
| Mingjun Yang and Gonghua Tan (1991) |
| Zeng et al. (2000) |
| Liyan Zhang and Jigang Tang (1996) |
Czech Republic | |
| Jakub Plasil |
| |
Germany | |
| Walenta (1992) |
| |
| |
| Walenta (1992) |
| |
| Frondel (1963) |
Indonesia | |
| Simon et al. (1997) |
Italy | |
| Menchetti S. (Alpi Apuane) |
Japan | |
| NAKAYAMA (1986) |
Kazakhstan | |
| Pekov et al. (1997) |
Peru | |
| Hyrsl et al. (2003) |
Russia | |
| Novoselov et al. (2010) |
| Nikolaev et al. (2016) |
South Korea | |
| Park et al. (1988) |
Switzerland | |
| Stalder et al. (1998) |
USA | |
| Eckel et al. (1997) |
| Eckel et al. (1997) |
| Eckel et al. (1997) |
| Lasmanis (1995) |
Uchucchacua Mine, Uchucchacua area, Oyón District, Oyón Province, Lima, Peru