Minerals: Building Blocks of Rocks Definition of a mineral Natural Inorganic Solid Possess an orderly internal structure of atoms Have a definite chemical composition Rock – any naturally occurring solid mass of mineral or mineral-like matter

Rocks are Aggregates of Minerals

Atoms: Building Blocks of Minerals Smallest particles of matter Elements Basic building blocks of minerals Over 100 are known Defined by their number of protons Groups of the same type of atoms

Periodic table of the elements

Minerals Physical properties of minerals Habit – common crystal shape Luster – appearance in reflected light Color Streak – color of mineral in powdered form Hardness – ability to resist scratching or abrasion Cleavage – tendency to break along planes of weak bonding

Metallic Luster: Galena

Color Color can be unreliable due to variations.

Streak

Crystal Shape, or Habit: Pyrite

Hardness: Mohs Scale

Cleavage: Micas

Minerals Physical properties of minerals Fracture – random pattern of breakage Specific gravity – mineral density Tenacity – resistance to cutting, breaking, bending, and deformation

Conchoidal fracture

Minerals Other properties Taste Smell Elasticity Malleability Double refraction Magnetism Feel Reaction with hydrochloric acid