Igneous Rocks
Igneous rocks form from hot liquid magma beneath the Earth’s surface. The magma either erupts from a volcano, cools and hardens into extrusive igneous rocks, or forms intrusive igneous rock when the hot magma is trapped beneath the earth’s surface, cools and hardens.
Extrusive igneous rocks typically have no or very small crystals such as pumice or obsidian. Intrusive rocks usually have visible grains such as granite or monzonite.
Igneous rocks make great stocking stuffers for geology fans. Shop today for your favorites.
Filed under: Geology / Earth Science, Geology Education, Rocks - Igneous, Sedimentary & Metamorphic on December 7th, 2011
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