UNIT 12 VOCABULARY (ROCKS AND MINERALS) 2015 1) Cementation: A process whereby compacted sediments bind and stick together and turn into rock. 2) Compaction: A process whereby sediments pack, crush, and settle under the action of gravity and pressure from overlying layers. 3) Sedimentary Rock: Rock made of layers of compressed organic and inorganic sediments. 4) Metamorphic Rock: Rock deep within Earth's crust that has been exposed to extreme heat and pressure causing changes to its appearance, structure, and composition. 5) Igneous Rock: Rock formed when heated magma or lava cools and hardens. 6) Mineral: A naturally formed, inorganic solid that has a specific chemical formula and repeating three-dimensional structure. 7) Magma: Melted rock material beneath Earth's surface. 8) Lava: A result of molten rock material pushed to Earth's surface by volcanic action. 9) Luster: The way the surface of a mineral reflects light; either metallic or non-metallic such as silky, dull, glassy, or resinous. 10) Hardness: A measure of scratch resistance of various minerals through the ability of a harder minerals to scratch a softer minerals for identification; a set of ten minerals used as a standard of hardness against which an unknown mineral's hardness is compared (Known as Mohs Hardness Scale). 11) Streak: The color of a mineral in powdered form. 12) Crystal Formation: Geometric shape of a mineral that reflects its internal crystalline arrangement of atoms. UNIT 12 VOCABULARY (ROCKS AND MINERALS) 2015 1) Cementation: A process whereby compacted sediments bind and stick together and turn into rock. 2) Compaction: A process whereby sediments pack, crush, and settle under the action of gravity and pressure from overlying layers. 3) Sedimentary Rock: Rock made of layers of compressed organic and inorganic sediments. 4) Metamorphic Rock: Rock deep within Earth's crust that has been exposed to extreme heat and pressure causing changes to its appearance, structure, and composition. 5) Igneous Rock: Rock formed when heated magma or lava cools and hardens. 6) Mineral: A naturally formed, inorganic solid that has a specific chemical formula and repeating three-dimensional structure. 7) Magma: Melted rock material beneath Earth's surface. 8) Lava: A result of molten rock material pushed to Earth's surface by volcanic action. 9) Luster: The way the surface of a mineral reflects light; either metallic or non-metallic such as silky, dull, glassy, or resinous. 10) Hardness: A measure of scratch resistance of various minerals through the ability of a harder minerals to scratch a softer minerals for identification; a set of ten minerals used as a standard of hardness against which an unknown mineral's hardness is compared (Known as Mohs Hardness Scale). 11) Streak: The color of a mineral in powdered form. 12) Crystal Formation: Geometric shape of a mineral that reflects its internal crystalline arrangement of atoms.