Flexi Says: Some minerals can be identified with little more than the naked eye. We do this by examining the physical properties of the mineral, which include:
Color: the color of the mineral.
Streak: the color of the mineral’s powder (this is often different from the color of the whole mineral).
Luster: shininess.
Density: mass per volume, typically reported in "specific gravity," which is the density relative to water.
Cleavage: the mineral’s tendency to break along planes of weakness.
Fracture: the pattern in which a mineral breaks.
Hardness: which minerals it can scratch and which minerals can scratch it.
Tenacity: Capacity of mineral to resist breakage.
