Langbahn Team – Weltmeisterschaft

Chaidamuite

Chaidamuite
General
CategorySulfate minerals
Formula
(repeating unit)
ZnFe3+(SO4)2(OH)·4(H2O)
IMA symbolCdm[1]
Strunz classification7.DC.30
Crystal systemTriclinic
Crystal classPedial (1)
(same H-M symbol)
Space groupP1
Unit cella = 7.309(2) Å,
b = 7.202(2) Å,
c = 9.691(3) Å;
α = 89.64(3)°, β = 105.89(1)°,
γ = 91.11(1)°; Z = 2
Identification
ColorBrown to yellow-brown
Crystal habitTabular pseudocubic crystals and granular masses; pseudomonoclinic
CleavageOn {001} and {100}, perfect.
Fractureconchoidal
Mohs scale hardness2.5–3
LusterVitreous
StreakPale yellow
DiaphaneityTranslucent
Optical propertiesBiaxial (+)
Refractive indexnα = 1.632 nβ = 1.640 nγ = 1.688
Birefringenceδ = 0.056
PleochroismStrong: X= pale yellow, colorless; Y= pale yellow; z= Brownish yellow
2V angle44°
References[2][3][4][5]

Chaidamuite is a rare zinc – iron sulfate mineral with chemical formula: ZnFe3+(SO4)2(OH)·4H2O.

It was first described for an occurrence in the Xitieshan mine south of Mt. Qilianshan in the Chaidamu basin, Qinghai Province, China and was named for the locality. It occurs as an oxidation phase in a lead zinc deposit. In the type locality it is associated with the rare minerals: coquimbite, copiapite, butlerite and zincobotryogen.[5] In addition to the Chinese occurrence, it has been reported from the Getchell Mine in the Potosi District in Humboldt County, Nevada.[3]

References

  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ Li, W.M., and Wang, Q.G. (1990) Determination and Refinement of the Crystal Structure of Chaidamuite (Issue 5). Science in China Series B-Chemistry, 33, 623–630
  3. ^ a b Mindat.org
  4. ^ Webmineral data
  5. ^ a b Handbook of Mineralogy

Bibliography

  • Clark, A.M. (1993) Hey's Mineral Index (3rd edition). Alphabetical Index of Mineral Species, Varieties and Synonyms and Chemical Classification. 121 p. Chapman & Hall, New York, NY.
  • Jambor, J.L., and Burke, E.A.J. (1990) New Mineral Names. American Mineralogist, 75, 1431–1437.
  • Li, W., Chen, G., and Peng, Z. (1986) Chaidamuite. Acta Mineralogica Sinica, 6, 109.
  • Li, W.M., and Wang, Q.G. (1990) Determination and Refinement of the Crystal Structure of Chaidamuite (Issue 5). Science in China Series B-Chemistry, 33, 623–630
  • Mandarino, J.A., and de Fourestier, J., (2005) Mineral Species First Found in People's Republic of China. (No. 2). Rocks and Minerals, 80, 114–117.