Characteristics of Minerals

Minerals are… Naturally occurring (not man made) Yes - Diamonds No – Cubic Zirconia

Minerals are… Inorganic (non-living) Mineral Not a mineral From non-living carbon From carbon of plants Mineral Not a mineral

Minerals are… Solid – definite volume, definite shape

Minerals are… Solid – definite volume, definite shape Definite chemical (fixed) composition A mineral always contains certain elements in definite proportions

Minerals have… Crystal structure – a repeating pattern of particles

Write a definition for a mineral A mineral is…

Write a definition for a mineral A mineral is a naturally occurring, inorganic solid with a crystal structure and a definite chemical composition.

Solid Naturally Occurring Inorganic Composition Element or Compound

Identifying Minerals Color

Identifying Minerals Color Streak – color of the mineral as a powder - we use a streak plate (unglazed porcelain) to create the powder How do we perform a Streak test everyday? Using a pencil.

Identifying Minerals Luster – how light reflects off the surface of a mineral Metallic (like metal) Nonmetallic – glassy, waxy, greasy, pearly, dull, silky, earthy

Identifying Minerals Density – mass per unit volume density= mass/volume

Identifying Minerals Softest (1) - Hardest (10) Density – mass per unit volume density= mass/volume Mass = 72 g Volume = 9 cm3 Density = ? 8 g/cm3 Hardness – how easily a mineral can be scratched Moh’s Scale Softest (1) - Hardest (10)

Mohs Hardness Scale

Identifying Minerals Crystal systems cubic tetragonal hexagonal orthorhombic monoclinic triclinic

Identifying Minerals Breakage Cleavage - breaks along flat surfaces Fracture – breaks in an irregular way

Identifying Minerals Special Properties Magnetic (magnetite) Optical properties (some calcite) Fizzes with HCl (calcite) Taste (halite) Smell (sulfur)