spodumene

Spodumene is a lithium aluminum inosilicate mineral with the chemical formula LiAlSi2O6. It is a member of the pyroxene group and is an important primary source of lithium. Spodumene forms in granitic and pegmatitic rocks and occurs as colorless to pale crystals that can be highly colored by trace elements.

Crystallography and properties: It crystallizes in the monoclinic system and typically forms elongated prismatic crystals with a vitreous luster. It has a hardness of 6 to 6.5 on the Mohs scale and exhibits imperfect cleavage in one direction. Spodumene is pleochroic, showing different colors when viewed from different angles.

Colors and varieties: The mineral has several well-known varieties. Kunzite is a pink to purplish-pink variety, often pale in color; hiddenite is the green variety, prized as a gemstone; triphane is the colorless to pale variety.

Occurrence and distribution: Spodumene occurs primarily in lithium-rich pegmatites associated with quartz, feldspar, lepidolite, and beryl. It is mined in several countries and is a major ore of lithium.

Uses and significance: The principal economic use of spodumene is as a source of lithium for batteries, ceramics, and glass. When gem-quality, kunzite and hiddenite are cut as decorative stones, though some kunzites are heat-treated to enhance color.