Gem Pocket main content.

Gem Pocket

Part of Hall of Gems.


Crystal-filled cavities, or pockets, occasionally are found in pegmatite rock. This rock forms as the last remaining liquid, rich in rare metals and volatile substance, crystallizes after the cooling of great bodies of igneous rock. Presence of these volatiles and slow loss of heat to the surroundings allow giant crystals to form. Rarely, the process results in magnificent gem crystals projecting into clay-filled openings at the core of the pegmatite.