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Scoria

What is Scoria?

Scoria is a dark-colored, vesicular, extrusive igneous rock. The vesicles are a result of trapped gas within the melt at the time of solidification. It often forms as a frothy crust on the top of a lava flow or as material ejected from a volcanic vent and solidifying while airborne.

scoria

Scoria: 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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