Sec' 9'2 Mineral Identification

1
Sec. 9.2- Mineral Identification

• How can you tell one mineral from another?

2
Mineral Properties and Chemical Structure

• physical properties of minerals depend on
• Chemical Makeup
• Crystal Structure- arrangement of its atoms,
  ions, molecules

3
Properties of Minerals

• Luster- the way light reflects off a minerals
  surface
• Metallic
• Nonmetallic- pearly, silky, glassy
• Streak- color of the powder a mineral leaves on a
  streak plate
• a minerals streak is the same regardless of its
  color

4
Properties of Minerals- cont

• Color- outside appearance
• Hardness- ability of a mineral to resist being
  scratched
• Mohs Hardness Scale
• Overhead

5
Properties of Minerals- cont

• Mineral Breakage
• Cleavage- when a mineral breaks along a flat
  surface (plane)
• Fracture- when a mineral breaks leaving an uneven
  surface
• Curved- Conchoidal- used to make cutting tools

6
Properties of Minerals- cont

• Density Specific Gravity
• What is the equation for density?
• What is the density of water?
• Specific Gravity (SG)- compares the density of a
  mineral to the density of water.
• SG a minerals density without units
• Heft- minerals weight
• Practice problems- Overhead

7
Properties of Minerals- cont

• Special Unique Properties
• Magnetic
• Fluorescent- exposure to ultra-violet light
  causes mineral to glow
• Reacts with acid
• Soapy feel