Minerals A mineral: occurs naturally Is inorganic Is solid Has a crystal structure Has a definite chemical composition

Minerals There are 3000 minerals. 100 are common. 20 minerals make up most of the rock’s of Earth’s crust (rock-forming minerals).

Mineral Formation Minerals form through: Crystallization of melted materials. Crystallization of materials dissolved in water.

Crystals Repeating patterns of a mineral’s particles that form a solid.

Minerals All minerals contain certain elements in definite amounts. Most minerals are compounds (two or more elements). Silver and gold are considered minerals.

The Mohs hardness scale ranks ten minerals from softest to hardest. Talc 1 Gypsum 2 Calcite 3 Fluorite 4 Apatite 5 Feldspar 6 Quartz 7 Topaz 8 Sapphire 9 Diamond 10 The Mohs hardness scale ranks ten minerals from softest to hardest.

Minerals are ranked according to: Color

Streak– the color of a mineral’s powder.

Luster – how shiny a mineral is.

Density—mass per unit volume (specific gravity)

Cleavage – breaking of a mineral along a regular line.

Fracture – irregular breaking of a mineral.

Fluorescence Minerals that glow under ultraviolet light.

Magnetism Magnetism occurs naturally in some minerals, such as magnetite.