In geology, a rock is a naturally occurring solid mass of minerals or mineraloid matter. Rocks are made up of mineral grains, which are crystalline solids formed from atoms chemically bonded into an orderly structure. Some rocks also contain mineraloids, which are rigid, mineral-like substances.  Some common rocks include: Granite, Basalt, Limestone, Sandstone.  Here are some types of rocks: Igneous rocks: Form when hot, molten rock crystallizes and solidifies. The word "igneous" comes from the Latin word for fire. Igneous rocks can be divided into two groups, intrusive or extrusive,... Show more

In geology, a rock is a naturally occurring solid mass of minerals or mineraloid matter. Rocks are made up of mineral grains, which are crystalline solids formed from atoms chemically bonded into an orderly structure. Some rocks also contain mineraloids, which are rigid, mineral-like substances. 

Some common rocks include: Granite, Basalt, Limestone, Sandstone. 

Here are some types of rocks:
Igneous rocks: Form when hot, molten rock crystallizes and solidifies. The word "igneous" comes from the Latin word for fire. Igneous rocks can be divided into two groups, intrusive or extrusive, depending on where the molten rock solidifies.
Metamorphic rocks: Form when existing rocks have undergone pressure and/or temperature changes so that their original mineralogy has been changed. Metamorphic rocks can be identified from their physical features.
Foliated rocks: Have a layered or banded structure, produced by exposure to heat and directed pressure. Examples include slate, schist, and gneiss

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