Kalinite
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, 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".
| 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 |
| IMA symbol | Kli |
| Strunz classification | 7.CC.15 |
| Dana classification | 29.5.4.2 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) (same H-M symbol) |
| 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 | |
A proposal to remove recognition of kalinite as a mineral species was submitted to the International Mineralogical Association; however, kalinite is still on the list of approved minerals. Many older samples, however, have been found to be potassium alum.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.