Sengierite

Summary

Sengierite is a rare oxide and hydroxide mineral, chemically a copper and uranyl vanadate, belonging to the carnotite group. Its chemical formula is Cu2(OH)2[UO2|VO4]2·6H2O.[2][3]

Sengierite
General
CategoryOxide and Hydroxide
Formula
(repeating unit)
Cu2(OH)2[UO2|VO4]2·6H2O
IMA symbolSgi[1]
Crystal systemMonoclinic
Space groupMonoclinic 2/m
Identification
ColorOlive-green, yellowish green
Crystal habitFlattened thin plates, coatings
CleavagePerfect on {001}
TenacityBrittle
Mohs scale hardness2.5
LusterAdamantine, vitreous
StreakLight green
DiaphaneityTransparent
Specific gravity4.05
Density4.05 g/cm3 (measured)
4.1 g/cm3 (calculated)
Refractive indexnα = 1.760 – 1.770 nβ = 1.920 – 1.940 nγ = 1.940 – 1.970
PleochroismX: Bluish green,
Y: Olive-green,
Z: Yellowish green to colorless
2V angleMeasured: 37° to 39°, Calculated: 36°
Other characteristics Radioactive

Sengierite was first discovered at the Luiswishi Mine about 20 kilometres (12 mi) north of Lubumbashi in Katanga Province in the Democratic Republic of the Congo and was first described in 1949 by Johannes F. Vaes and Paul F. Kerr, the mineral was named after Edgar Sengier (1879–1963), a former Director of the Union Minière du Haut Katanga.[4]

References edit

  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. ^ "Sengierite: Sengierite mineral information and data". mindat.org. Retrieved 2018-08-09.
  3. ^ John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, and Monte C. Nichols, Eds., Handbook of Mineralogy, Mineralogical Society of America, Chantilly, VA 20151-1110, USA. PDF
  4. ^ J. F. Vaes; Paul F. Kerr (1949). "Sengierite: a preliminary description" (PDF). American Mineralogist. 34: 109–120.

Bibliography edit

  • Palache, P.; Berman H.; Frondel, C. (1960). "Dana's System of Mineralogy, Volume II: Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. (Seventh Edition)" John Wiley and Sons, Inc., New York, pp. 1047–1048.