Mineral Identification Chapter 5 Mineral Identification

Physical Properties Properties that can be measured. Ex) color, texture, shape, density

Physical Properties of a Mineral Hardness A measure of how easily a mineral can be scratched Soft mineral: Talc Hard mineral: Diamond

Moh’s Scale of Hardness

Luster The way a mineral reflects light Can be metallic or non-metallic

Streak The color of a mineral in powdered form The mineral is rubbed across an unglazed porcelain tile (streak plate) Only works for minerals that are softer than the streak plate

Cleavage Minerals that break along smooth flat surfaces

Fracture Minerals that break along uneven, rough or jagged edges

Color Good starting indicator but not good when used by itself

Other Properties Some minerals have special properties Magnetite- attracted to magnets Calcite- produces a double image fizzes when HCl is applied

Other Properties Fluorescence Phosphorescence Glow when viewed under ultraviolet light Examples: fluorite, calcite Phosphorescence Will continue to glow even after the ultraviolet light is removed Examples: sphalerite, Willemite

Other Properties Radiation Give off subatomic particles that can be detected by a Geiger counter Exposure is dangerous to living organisms Examples: carnotite, uraninite