Granite pegmatite main content.

Granite pegmatite

Granite pegmatite_HERO

Exhibition Text

This rock formed deep in the crust, near the top of a crystallizing magma chamber.  It is composed of the minerals quartz (gray), orthoclase (pink), albite (white), and mica (dark and platy). The larger crystals grew more slowly than the smaller crystals.

AMNH collection

For Educators

Topic: Earth Science

Subtopic: Earth Formation/Evolution

Keywords: Minerals, Pegmatites, Physical geology

Audience: General