lepidolite

Lepidolite (KLi2Al(Al,Si)3O10(F,OH)2) is a lilac or rose-violet colored phyllosilicate mineral of the mica group that is a secondary source of lithium. It is associated with other lithium-bearing minerals like spodumene in pegmatite bodies. It is one of the major sources of the rare alkali metals, rubidium and caesium.
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Noun
1. a mineral of the mica group; an important source of lithium
(hypernym) mica, isinglass
(substance-meronym) lithium, Li, atomic number 3

n. lepidolite

(n.)
A species of mica, of a lilac or rose-violet color, containing lithia. It usually occurs in masses consisting of small scales. See Mica.
  

General Information:
 Chemical Formula:
K(Li,Al)3(Si,Al)4O10(F,OH)2
 Composition:
(Molecular Weight = 386.31 gm)
Potassium 10.12 % K 
Lithium 3.59 % Li
Aluminum 6.98 % Al
Silicon 29.08 % Si
Hydrogen 0.52 % H 
Oxygen 49.70 % O 
 Empirical Formula:
KLi2AlSi4O10(OH)2
 Environment:
Lithia-bearing pegmatites.
 Locality:
Pala, San Diego Co., California, USA.
 Name Origin:
From the Greek lepidion - "scale" and lithos - "stone."
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
colorless, gray white, grayish, yellowish, or white.
 Density:
2.8 - 2.9, Average = 2.84
 Diaphaniety:
Translucent
 Habits:
Platy - Sheet forms (e.g. micas)., Foliated - Two dimensional platy forms., Massive - Uniformly indistinguishable crystals forming large masses.
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luminescence:
None.
 Luster:
Vitreous - Pearly
 Streak:
white
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