Petalite

Availability

Sold

Size

5 x 3 x 1 cm - Miniature 

Formula

LiAlSi₄O₁₀ (RRUFF)

Locality

Taquaral, Itinga, Minas Gerais, Brazil

A water clear crystal fragment of this rare lithium aluminosilicate found exclusively in granitic (LCT) pegmatites. Lithium in pegmatites is usually characterized by one of the primary lithium minerals: Spodumene or Petalite and to a lesser extent Amblygonite-Montebrasite. Lithium pegmatites are rare and constitute about 1-2% of all pegmatites. Most lithium pegmatites are zoned and usually occur at the furthest extents from the parent source and usually intrude metamorphic rock. Rarely do the minerals Petalite and Spodumene occur in the same pegmatite since Spodumene is stable at higher pressures and moderate temperature unlike Petalite (high T and moderate P)...then there is the secondary lithium mineral Eucryptite which is stable at low P and T. See Cerny and/or London...