RocksGroup1

A rock is a solid natural material that is hard or soft that has a distinctive mineral composition.

=== Sedimentary Rocks form from sediments deposited by water or air. Pebbles and other particles pressure and cement together creating the sedimentary rock. Some examples include limestone, sandstone, and conglomerate. You can identify a sedimentary rock by testing it with acid, flat or curved layers, and by texture and composition. ===

=== Metamorphic Rocks form from heat and pressure deep in the earth. You can identify these rocks by it's texture and composition, barely any fossils, and may have bands of dark or light minerals. Some examples include marble, slate and schist. ===

Igneous Rock Facts :

 * **igneous rocks are one of the three main rock types.**
 * **they are formed by magma being cooled or becoming solid.**
 * **some examples include pumice and pegmatite**
 * ======**they may form with or without crystallization, either intrusive or extrusive.** ======
 * ===== **When an active volcano is in the processes of irrupting, the rock that is being exploded out of the the volcano shots up into the air. While the rock is shot into the air, it quickly crystalizes.** =====
 * ===== **The rock now has a glassy/shiny look to it. Igneous rocks make up approximately 90% of the upper part of the Earth's crust, but their great abundance is hidden on the Earth's surface by a relatively thin but widespread layer ofsedimentary and metamorphic rocks.** =====

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