Mineral Identification
What is a Mineral? A naturally occurring, inorganic solid with a definite chemical composition and an orderly arrangement
Crystalline Forms The internal arrangement of atoms or ions determines the shape of the crystal
How do minerals form? Crystallization – when particles dissolve in a liquid or melt softly and reform in the shape of crystals
Rock Forming Minerals Silicate- a member of this group contains silicon and oxygen in their crystal formation Examples: Quartz, Feldspar, Olivine, Mica Nonsilicate – a member of this group does not contain silicon Examples: Calcite, Halite
Color
The way a mineral reflects or absorbs light at its surface Luster The way a mineral reflects or absorbs light at its surface Metallic – the shiniest luster Waxy, Silky, Pearly, Vitreous (glassy) Earthy, Dull
Streak – the color that it leaves behind
Hardness How strong a mineral is compared to other known materials
Cleavage Cleavage – breaks with smooth flat surfaces
Fracture Fracture - breaks in uneven surfaces
Density Mass divided by volume- how tightly the molecules are packed together
Other test? Smell – rotten eggs - Sulfur Taste – only if safe - Halite Chemically Reactive – bubbles in HCl acid - Calcite