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rock-forming minerals

The approximately 20 minerals that make up most of the rocks of the Earth's crust.


a light-colored rock that has a high silica content.


dark-colored rock that is low in silica


The particles of minerals or other rocks that give a rock its texture


the look and feel of a rock's surface

Igneous Rock

A type of rock that forms from the cooling of magma or lava

sedimentary rock

A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together

metamorphic rock

A type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions

extrusive rock

is igneous rock formed from lava on the Earth's surface.

intrusive rock

is igneous rock that formed when magma hardened beneath the Earth's surface.


a scientist who studies the Earth, especially as it relates to rocks

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