What is Spodumene?
Spodumene is a lithium aluminium silicate and a major pegmatite mineral, known in gem form as Kunzite or Hiddenite and in crystals for long prismatic habits.
Mineralogy and crystal structure
Reference formula: LiAlSi2O6. Spodumene is monoclinic and strongly pleochroic in gem varieties. Kunzite and Hiddenite are commercial varieties, not separate mineral species, and colour can fade with light or heat in some material. Spodumene is classified with silicates and has a monoclinic crystal system. Typical hardness is 6.5–7 on the Mohs scale and specific gravity is approximately 3.1–3.2.
Colour, lustre and habit
Typical colours include colourless, white, pink, lilac, green, yellow. The usual prismatic, bladed, granular habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Spodumene forms in or is associated with lithium-rich granitic pegmatites and evolved magmatic cavities. Important documented localities include Brazil, Afghanistan, Pakistan, Madagascar, the United States and Australia.
One lithium mineral, several gem identities
Spodumene connects the battery-metal story of lithium-rich pegmatites with the jewellery market. Transparent crystals, pleochroism and named varieties make it commercially versatile.
Collecting and care
Protect from impact because of strong cleavage. Avoid heat and prolonged intense light, and clean valuable gems gently with warm soapy water.
