TrekGEO > Mineral Trail > Occurrence > Rare-element Pegmatite (Albite-Spodumene)

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Rare-element Pegmatite (Albite-Spodumene)

Chemical Process (Liquid-phase Growth) - Closed system under ground (Melt precipitation)




Albite-Spodumene type < Lithium subclass < (LCT family) < Rare-element class < Granitic pegmatite

Required Geological Setting

Plutonic rocks


Pegmatites formed by fractional crystallization of S-type granite magma associated with upper Greenschist facies to Amphibolite facies in Barrovian-type middle-P metamorphism. The albite-spodumene type pegmatites are formed at slightly deep 0.3-0.4 Gpa and lower temperature circumstance whereas other rare-element class pegmatites emplaced at shallow depth. This formation condition is almost same as the spodumene subtype of the complex type, but more abundant in albite and quartz than K-feldspar. Pegmatites are massive and pockets are very rare. The internal structure of albite-spodumene type pegmatites shows simple zoning with the characteristic oblique arrangement of spodumene and K-feldspar crystals to the tabular pegmatite bodies. The albite-spodumene type is characterized by extremely abundant Li.

Mineral Assemblages (Major minerals)

Quartz, Orthoclase, Microcline, Albite, Muscovite, (Almandine)

Mineral Assemblages

Spodumene, (Cassiterite, Beryl, Columbite-(Fe), Tantalite-(Fe))

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