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If Rocks Could Talk

Three Types of Rock

Rocks fall into these three groups:
Igneous , Sedimentary , and Metamorphic

Igneous rocks are formed from melted rock deep inside the Earth.

rocks including kimberlite, lherzolite with basalt crust, obsidian, granite, pegmatite, pumice, basalt, gabbro, rhyolite, and dacite
rocks including kimberlite, lherzolite with basalt crust, obsidian, granite, pegmatite, pumice, basalt, gabbro, rhyolite, and dacite
rocks including kimberlite, lherzolite with basalt crust, obsidian, granite, pegmatite, pumice, basalt, gabbro, rhyolite, and dacite

Sedimentary rocks are formed from layers of sand, silt, dead plants, and animal skeletons.

rocks including glacial conglomerate, sandstone, shale, chalk, Shelly limestone, anthracite, and banded iron
rocks including glacial conglomerate, sandstone, shale, chalk, Shelly limestone, anthracite, and banded iron
rocks including glacial conglomerate, sandstone, shale, chalk, Shelly limestone, anthracite, and banded iron

Metamorphic rocks formed from other rocks that are changed by heat and pressure underground.

rocks including slate, jadeite, garnet amphibolite, schist, marble, gneiss, deformed conglomerate, sphalerite ore rock, and eclogite
rocks including slate, jadeite, garnet amphibolite, schist, marble, gneiss, deformed conglomerate, sphalerite ore rock, and eclogite
rocks including slate, jadeite, garnet amphibolite, schist, marble, gneiss, deformed conglomerate, sphalerite ore rock, and eclogite
Image Credits:
All rocks courtesy of AMNH; All rocks, © AMNH.