Rock and mineral characteristics

what are the five characteristics a mineral must have

natural occuring, inorganic, has a crystal structure, solid, and a definite chemical composistion

What are the eight ways to identify a mineral

color, streak, luster, density, hardness, crystal systems, clevage and fracture, and special properties

streak

the color of a mineral's powder

luster

the term used to describe how light is reflected from a mineral's surface

Mohs hardness scale

a scale that ranks ten minerals from softest to hardest

clevage

a mineral that splits easily along flat surfaces

fracture

a mineral that breaks apart in an irregular way

what are the five special properties

magnetism, fluorescence, optical properties, reactivity, radioactivity, and electrical properties

geode

a rounded, hollow rock that is often lined h mineral crystals

crystallization

the process by which atoms are arranged to form a material with a crystal structure

magma

molten material from inside the Earth

Lava

magma that reaches the surface

how do minerals form from magma and lava

as hot magma cools inside Earth, or as lava hardens on the surface

solution

a mixture in which one substance is dissolved in another

what occurs when elements and compounds that are dissolved in water leave a solution

crystallization

vein

a narrow channel or slab of a mineral that is different from the surrounding rock

gemstone

a hard, colorful mineral that has a glassy luster

ore

a rock that contains a metal or other useful minerl that can be mined and sold at a profit

smelting

when an ore is mixed with other substances and then melted

alloy

a solid mixture of two or more elements, at least one of which is a metal

texture

the look and feel of the rock's surface

what are the three different things geologists use to describe a rock's texture

grain size, grain shape, and grain pattern

what are the three groups geologists classify rocks into

igneous rock, sedimentary rock, and metamorphic rock

igneous rock

forms from the cooling of magma or lava

sedimentary rock

forms when particles of other rocks or the remains of plants and animals are pressed and cemented together

metamorphic rock

forms when an existing rock is changed by heat, pressure, or chemical reaction

how are igneous rocks classified

according to their orgin, texture, and mineral compossistion

what are the two kinds of igneous rock

extrusive rock and intrusive rock

extrusive rock

igneous rock formed from lava that erupted onto Earth's surface

intrusive rock

igneous rock that is formed when magma hardens beneath Earth's surface

silica

a material formed from oxygen and silicon

sediment

small, solid piecesof material that come from rock or living things

what is the process in which a sedimentary rock is formed

erosion, deposistion, compaction, and cemention

erosion

running water, wind or ice loosen and carry away fragments of rock

deposistion

the process by which sediment settles out of the water or wind carrying it

compaction

the process that presses sediment together

cemention

the process in which dissolved minerals crystallize and glue particles of sediment together

what are the three groups of sedimentary rock

clastic rocks, organic rocks, and chemical rocks

clastic rock

a sedimentary rock that forms when rock fragments are squeezed together.

organic rock

forms where the remains of plants and animals are deposited in thick layers

chemical rock

forms when minerals that are dissolved in a solution crystallize

coral reef

skeletons that grow together to form a structure

how do geologists classify metamorphic rock

according to the arrangment of the grains that make up the rocks

what are the two kinds of metamorphic rocks

foliated rocks and nonfoliated rocks

foliated

metamorphic rocks that have their grains arranged in parallel layers

rock cycle

a series of processes on Earth's surface and in the crust and mantle that slowly change rocks from one kind to another