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Unnamed (Ir-Os Sulphide I)

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Formula:
(Ir,Os)S2
Colour:
steel gray to silver white
Lustre:
Metallic
Crystal System:
Isometric
Appears to be the Ir analogue of erlichmanite and laurite, but the synthetic analogue is different in terms of structure (orthorhombic). Stoichiometrically similar/identical to iridisite (rejected) and 'UM1978-16-S:IrOsPtRu'.

Found as grains within Pt-bearing chromite ore mainly in dunite at locality "C", China.

Compare kashinite.


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Unique IdentifiersHide

Mindat ID:
35889
Long-form identifier:
mindat:1:1:35889:7

Physical Properties of Unnamed (Ir-Os Sulphide I)Hide

Lustre:
Metallic
Colour:
Steel gray to silver white
Hardness:
VHN100=1200 - Vickers
Comment:
Variable, depends on composition
Tenacity:
Brittle

Optical Data of Unnamed (Ir-Os Sulphide I)Hide

Reflectivity:
WavelengthR1 (%)
480nm46.2%
500nm44.8%
520nm43.8%
540nm43.0%
560nm42.5%
58nm42.2%
600nm42.0%
620nm41.8%
640nm41.6%
660nm41.5%
680nm41.5%
700nm41.5%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 46.2%.
Colour in reflected light:
greyish white with bluish tint

Chemistry of Unnamed (Ir-Os Sulphide I)Hide

Mindat Formula:
(Ir,Os)S2
Element Weights:
Element% weight
Ir74.983 %
S25.017 %

Calculated from ideal end-member formula.
Elements listed:
Ir, Os, S - search for minerals with similar chemistry

Crystallography of Unnamed (Ir-Os Sulphide I)Hide

Crystal System:
Isometric
Class (H-M):
m3 (2/m 3) - Diploidal
Space Group:
Pa3
Cell Parameters:
a = 5.640 Å
Unit Cell V:
179.41 ų (Calculated from Unit Cell)
Comment:
space group not sure

Synonyms of Unnamed (Ir-Os Sulphide I)Hide

Other InformationHide

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 Unnamed (Ir-Os Sulphide I)Hide

References for Unnamed (Ir-Os Sulphide I)Hide

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