Kalinite

Not to be confused with kaolinite.
Kalinite

Kalinite from the Virgin Valley District, Nevada, USA. Specimen size 5.4 cm
General
Category Sulfate minerals
Formula
(repeating unit)		 KAl(SO4)2·11H2O
Strunz classification 7.CC.15
Dana classification 29.5.4.2
Crystal system Monoclinic
Crystal class Prismatic (2/m)
H-M symbol: (2/m)
Space group C2/c
Unit cell a = 19.92(16), b = 9.27(3)
c = 8.304(13) Å
β = 98.79(19)°; Z = 4
Identification
Formula mass 456.37 g/mol
Color White to pale blue
Crystal habit Fibrous
Fracture Conchoidal
Mohs scale hardness 2 to 2.5
Luster Vitreous
Streak White
Diaphaneity Transparent
Specific gravity 1.75 (observed) 2.0 (calculated)
Optical properties Biaxial (-)
Refractive index nα = 1.429 to 1.430, nβ = 1.452, nγ = 1.456 to 1.458
Birefringence None
2V angle 52° (measured), 82° (calculated)
Solubility Soluble in water
Other characteristics Not fluorescent, barely detectable radioactivity
References [1][2][3][4]

Kalinite is a mineral composed of hydrated potassium aluminium sulfate (a type of alum). It is a fibrous monoclinic alum, distinct from isometric potassium alum,[5] named in 1868. Its name comes from kalium (derived from Arabic: القَلْيَه al-qalyah “plant ashes”) which is the Latin name for potassium, hence its chemical symbol, "K".

A proposal to remove recognition of kalinite as a mineral species is scheduled to be submitted to the International Mineralogical Association,[4] currently (March 2010), kalinite is still on the list of approved minerals.[6] Many older samples, however, have been found to be potassium alum.[2]

Environment

Kalinite is a rare secondary mineral observed in the oxidized zone of mineral deposits, as efflorescence on alum slates, in caves, and as a volcanic sublimate.[7] It is associated with jarosite, KFe3+3(SO4)2(OH)6, and cuprian melanterite (pisanite), (Fe2+,Cu2+)SO4·7H2O, at Quetena, Chile.[8]

References

  1. ↑ Gaines et al (1997) Dana’s New Mineralogy, Wiley
  2. 1 2 http://www.handbookofmineralogy.org/pdfs/kalinite.pdf
  3. ↑ http://www.webmineral.com/data/Kalinite.shtml
  4. 1 2 http://www.mindat.org/min-2137.html
  5. ↑ American Mineralogist (1923) 8:15
  6. ↑ http://rruff.info/ima
  7. ↑ American Mineralogist (1927) 12:14
  8. ↑ American Mineralogist (1938) 23:721
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