Granite (#3) main content.

Granite (#3)

Part of Hall of Minerals.

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This specimen is an example of a rock that formed in a magmatic environment.

Magmatic: Granitic Minerals
Magmas crystalizing between 600°C, and 900°C, are formed within Earth’s crust and contain minerals different in kind from those occurring in gabbro and similar dark-colored igneous rocks.

One kind of magma crystallizing at these lower temperatures contains significant amounts of alkali elements, especially sodium, and produces several types of igneous rock. Best known is syenite. Minerals often formed in this rock type are corundum, nepheline, and sodalite. Another important kind of magma, enriched in potassium, crystallizes into