2. Minerals Essential question: What makes a mineral?

3. Minerals Mineral – Inorganic solid – Definite chemical composition – Definite crystal structure – Naturally occurring Graphite= C (Pencil) Diamond= C (Diamonds) Halite= NaCl (Salt) Hydrogen Oxide= H 2 O (Ice)

4. Properties 1.Hardness The Mohs hardness scale Diamond = 10 Talc = 1 2.Color Not used often FEW minerals can be ID’ed by eternal color 3.Streak The color of a minerals powder Streak plate Very useful – does not vary like external color

5. Properties 4.Luster How mineral reflects light Range = Luster, earthy, waxy, pearly 5.Density Mass per unit volume Water displacement 6.Crystal Shape 8 groups Number and angle of crystal faces

6. Properties 7.Cleavage and fracture The way a mineral breaks apart Cleavage = evenly Fracture = unusual 8.Special Properties Magnetism Radioactivity Electrical Fluorescent » Glow under UV radiation

7. Properties *****ALL Properties of ALL minerals are dependant on internal structure of atoms and compounds. ******