Crystal of lepidolite, Brazil

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.^[1] 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.^[2] Image File history File links Download high-resolution version (1113x894, 879 KB) Lepidolite. ... Image File history File links Download high-resolution version (1113x894, 879 KB) Lepidolite. ... The silicate minerals make up the largest and most important class of rock-forming minerals. ... Minerals are natural compounds formed through geological processes. ... For other uses, see Mica (disambiguation). ... General Name, Symbol, Number lithium, Li, 3 Chemical series alkali metals Group, Period, Block 1, 2, s Appearance silvery white/grey Atomic mass 6. ... Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate - LiAl(SiO3)2 - and is a source of lithium. ... This article or section does not cite its references or sources. ... The alkali metals are the series of elements in Group 1 (IUPAC style) of the periodic table (excluding hydrogen in all but one rare circumstance): lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... General Name, Symbol, Number caesium, Cs, 55 Chemical series alkali metals Group, Period, Block 1, 6, s Appearance silvery gold Atomic mass 132. ...

Physical Properties

Color: violet lombo pale pink to white, sometimes gray or yellow.

Luster: vitreous to pearly

Transparency: transparent to translucent.

Crystal System: monoclinic; 2/m.

Crystal Habits: include tabular to prismatic crystals with a prominent pinacoid termination. Lepidolite forms pseudo-hexagonal "books." Also as micaceous or granular masses.

Cleavage: perfect in one direction perpendicular to the c-axis.

Fracture: uneven.

Hardness: 2.5

Specific Gravity: 2.8+

Streak: white

Density:2.8-2.9 Average size 2.84

Associated Minerals: quartz, feldspar, spodumene, amblygonite, tourmaline. Quartz is one of the most common minerals in the Earths continental crust. ... Lunar Ferroan Anorthosite #60025 (Plagioclase Feldspar). ... Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate - LiAl(SiO3)2 - and is a source of lithium. ... Amblygonite is a fluorophosphate mineral, (Li,Na)AlPO4(F,OH), composed of lithium, sodium, aluminium, phosphate, fluoride and hydroxide. ... The tourmaline mineral group is chemically one of the most complicated groups of silicate minerals. ...

Notable Occurrences: Brazil; Ural Mountains, Russia; California; Tanco Pegmatite, Bernic Lake Manitoba, Canada.

References

1. ^ "Manual of Mineralogy, 20th Ed." by Cornelius Hurlbut and Cornelis Klein.
2. ^ H. Nechamkin, The Chemistry of the Elements, McGraw-Hill, New York, 1968.

See also: List of minerals Gem animals. ...