Spodumene

inosilicate

kunzite

Formula: LiAlSi2O6 inosilicate (chain silicate) pyroxene group
Kunzite is a variety of spodumene
Specific gravity: 3.1 to 3.2
Hardness: 6½ to 7
Streak: White
Colour: Colourless, white, pink and lilac (kunzite), green (hiddenite), yellow, brown
Solubility: Insoluble in hydrochloric, sulphuric and nitric acid
Environments:

Pegmatites

Spodumene is found almost exclusively as a primary mineral in lithium-rich pegmatites.

Alteration

At the White Picacho District, Arizona, USA, the alteration sequence for spodumene is
spodumene → eucryptite + albitemuscovite + albitemuscovite

petalite to spodumene and quartz
LiAlSi4O10 ⇌ LiAlSi2O6 + 2SiO2

spodumene, quartz and Na+ to albite and Li+
LiAlSi2O6 + SiO2 + Na+ → NaAlSi3O8 + Li+
Whether spodumene breaks down into albite or into eucryptite and albite depends largely on the presence or absence of quartz.

spodumene and Na+ to eucryptite, albite and Li+
2LiAlSi2O6 + Na+ → LiAlSiO4 + NaAlSi3O8 + Li+
Whether spodumene breaks down into albite or into eucryptite and albite depends largely on the presence or absence of quartz.

spodumene, K+ and H+ to muscovite, quartz and Li+
3LiAlSi2O6 + K+ + 2H+ → KAl3Si3O10(OH)2 + 3SiO2 + 3Li+
The direct conversion of spodumene to muscovite liberates silica, but quartz is not usually present in pseudomorphs of muscovite after spodumene, and this requires an explanation.

Common impurities: Fe,Mn,Mg,Ca,Na,K,H2O

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