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Pegmatite

What is Pegmatite?

Pegmatite is a light-colored, extremely coarse-grained intrusive igneous rock. It forms near the margins of a magma chamber during the final phases of magma chamber crystallization. It often contains rare minerals that are not found in other parts of the magma chamber.

Pegmatite: The specimen shown is about two inches (five centimeters) across.

The rock photos above were taken by Ann Bryant and are copyright by Geology.com.

Igneous Rocks

Andesite

Basalt

Diorite

Gabbro

Granite

Obsidian

Pegmatite

Peridotite

Pumice

Rhyolite

Scoria

Tuff

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Sedimentary Rocks: Photos and facts about clastic, chemical and organic sedimentary rocks.