Earth Science

The ability of a mineral to glow DURING and after exposure to ultraviolet light

The bending of light rays as they pass through a mineral

The ability of a mineral to continue to glow AFTER exposure to ultraviolet light

Atoms are bonded tightly together

The mineral will split into even sheets

4

QuartzFeldsparMicaCalcite Iron

halite

Gold and copper

90%

Silicate mineralsNonsilicate minerals

CarbonatesOxidesSulfidesSulfatesHalidesNative elements

SiliconOxygen

Feldspar is an exampleComposed to interconnected tetrahedrons

that form an intricate framework

Chemical composition

Pitchblende

feldspar

magnetite

Density

SiliconOxygen

SodiumCalcium

brilliant

lodestone

Garnet

The mineral with the higher number can scratch the lower number

Quartz is a framework silicate It contains only silicon-oxygen tetrahedraThe bonds between the tetrahedra are very

strong This makes quartz extremely hard

Feldspar is a framework silicateSome tetrahedra in feldspar have atoms of

metal instead of siliconThe bonds between these atoms are weaker

than those between silicon and oxygenTherefore, feldspar is not as hard as quartz