Identifying Minerals

Minerals can be identified by looking at their physical properties including: color, luster, streak, cleavage or fracture, and hardness

Color Minerals can come in a variety of colors Colors can be influenced by impurities Not the best way to identify minerals

Luster The way a surface reflects light Minerals can have metallic luster, shiny Minerals can have nonmetallic luster, dull

Streak Color of a mineral in powdered form Less impurities so it is a better way to identify a mineral

Cleavage and Fracture Cleavage – Tendency to break along smooth, flat surfaces Fracture – Tendency to break along unevenly curved or irregular surfaces

Hardness Resistance to being scratched Minerals are rated 1 to 10 10 is the hardest and 1 is the softest