Formula: LiAlSi2O6
Inosilicate (chain silicate), clinopyroxene subgroup, pyroxene group, lithium-bearing mineral
Kunzite is a pink gem variety of spodumene
Crystal System: Monoclinic
Specific gravity: 3.1 to 3.2 measured, 3.184 calculated
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
Common impurities: Fe,Mn,Mg,Ca,Na,K,H2O


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


The Peatfold pegmatite at Glenbuchat, Strathdon, Aberdeenshire, Scotland, UK, shows a distinctly zoned structure, broadly symmetrical around a central core of bright purple mica, probably lepidolite. The spodumene lens contains striated, fractured intergrown crystals of spodumene, associated with plentiful tourmaline. This occurrence of spodumene is thought to be the first substantiated report of the mineral from Scotland. (JRS 20.30-33).

At the White Picacho District, Arizona, USA, the alteration sequence for spodumene is
spodumeneeucryptite + albitemuscovite + albitemuscovite
(AM 67: 97-113).
The zoning sequence within the pegmatite goes from spodumene + quartz to spodumene + montebrasite + quartz to montebrasite + quartz (R&M 92.2.151)

At the Emmons pegmatite, Greenwood, Oxford county, Maine, USA, spodumene crystals to 50 cm are associated with amblygonite-montebrasite, pollucite and alkali-rich beryl. The Emmons pegmatite is an example of a highly evolved boron-lithium-cesium-tantalum enriched pegmatite (R&M 94.6.515). Talc pseudomorphs after spodumene have been found here (KL p235).

At Plumbago Mountain, Newry, Oxford County, Maine, USA, excavations and core-drilling have exposed a new albite-quartz-spodumene pegmatite, the Plumbago North pegmatite. It is spodumene-rich with more than 50 percent spodumene in some of the upper portions of the pegmatite. The exposed portion of the pegmatite is composed principally of quartz, albite, muscovite and spodumene. Microcline is sparse and occurs in the spodumene zone and rare miarolitic cavities. Montebrasite, beryl, cassiterite, almandine-spessartine series garnets, fluorapatite and columbite-group species are also present. Schorl, lepidolite and pollucite are rare. Columbite-group minerals include columbite-(Fe), columbite-(Mn) and tapiolite-(Fe). Triphylite pods to 50 cm across with associated iron-dominant secondary phosphate species are scattered across the spodumene-rich zone. Spodumene and montebrasite occur in gigantic crystals. One spodumene crystal exceeded 11 meters in length, and crystals in excess of 2 meters in length are common. Montebrasite also occurs in very large single crystal masses, with some exceeding 1.5 meters across (R&M 97.3.276).


petalite to spodumene and quartz
LiAlSi4O10 ⇌ LiAlSi2O6 + 2SiO2
(DHZ 4 p274)

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 (AM 67: 97-113).

spodumene and Na+ to eucryptite, albite and Li+
2LiAlSi2O6 + Na+ → LiAlSiO4 + NaAlSi3O8 + Li+
Whether spodumene breaks down into albite or into albite or into eucryptite and albite depends largely on the presence or absence of quartz (AM 67: 97-113).

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 (AM 67: 97-113).

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