Ch. 4 Sec. 2Ch. 4 Sec. 2How Minerals How Minerals

FormForm

geode• rounded hollow rock lined w/ mineral crystals

crystallization• process by which atoms are arranged to form material w/ crystal structure

2 ways minerals can form

crystallization of melted materials

(magma or lava cools)

crystallization of materials

dissolved in water(evaporation)

minerals from magma

factors thataffect crystal

size

rate at whichmagma cools

amount of gas magma

contains

chemical compositionof magma

slow cooling large crystals

rapid coolingsmall crystals

• hot magma or lava cools forms crystals

solution

•mixture in which one substance dissolves in another

magma heats water underground

minerals formed by evaporation

• water evaporates from solution leaving crystals of minerals

These huge selenite crystals in a cave in Mexico formed from the crystallization of minerals in a solution.

Crystal cave in Mexico

National Geographic

vein • narrow channel or slab of mineral that is different from surrounding rock

halite depositshalite deposits

• formed over millions of years when ancient seas evaporated

geode• rounded hollow rock lined w/ mineral crystals

crystallization• process by which atoms are arranged to form material w/ crystal structure

How do minerals form from magma and lava?

Minerals form as hot magma cools inside the crust, or as lava hardens on the surface. When these liquids cool to a solid state, they form crystals.

How do minerals form from water solutions?

Minerals form as hot magma cools inside the crust, or as lava hardens on the surface. When these liquids cool to a solid state, they form crystals.

minerals from magma

factors thataffect crystal

size

rate at whichmagma cools

amount of gas magma

contains

chemical compositionof magma

slow cooling large crystals

rapid coolingsmall crystals

• hot magma or lava cools forms crystals

vein • narrow channel or slab of mineral that is different from surrounding rock