1. Minerals and their characteristics

2. Physical Properties of Minerals Color: the color a mineral appears to the eye –Not effective in I.D.ing few minerals because … –Some are similar in color. –Others can have their color changed. –Some come in multiple colors. Streak: the color of a mineral in its powered form. –More effective than color

3. Physical Properties of Minerals LUSTER: the way a mineral reflects light. –Metallic Luster: shining like polished metal. (Ex: Pyrite, Galena, Hematite, Magnetite) –Non-metallic Luster: shining like polished glass, silk, wax, or any other shiny non-metal. (Ex: Diamond, Quartz, Opal.) –A mineral that does not reflect light is said to have an “earthy” luster.

4. Other acceptable adjectives for luster: –A–Adamantine (most lusterous, like diamond) –V–Vitreous (glassy) –D–Dull –G–Greasy –R–Resinous –P–Pearlescent –A–Adventurine (glittery) These terms are often combined (viterous greasy) Physical Properties of Minerals

5. Hardness: a mineral’s resistance to being scratched. Moh’s Hardness Scale: The hardness of minerals relative to each other/scratching implements. –The scale is from 1-10, with 1 being the softest and 10 being the hardest.

6. Physical Properties of Minerals Moh’s Scale MineralTools 1Talc Fingernail (2.5) 2Gypsum 3Calcite Steel Nail (4.5) (Avoid the point) 4Fluorite 5Apatite Glass (5.5) 6Feldspar 7Quartz Streak Plate (5-8) 8Topaz 9Corundum 10Diamond

7. Physical Properties of Minerals Cleavage the tendency of a mineral to split along a certain plane or planes. described in numbers of planes and angles of intersection.

9. Fracture when minerals don’t break along typical cleavage planes. EXAMPLES: Conchoidal: shell-like and smooth Hackly: rough, jagged edges Fibrous: breaks into strands

10. Special Properties of Minerals Texture Taste Smell Magnetic

11. Special Properties of Minerals Density: The amount of water it displaces. (Crystals with a metallic luster are generally denser.) Phosphorescence: Does it glow under black light? (Fluorite) Effervesces: Reacts by bubbling when exposed to acid (calcite, dolomite)