Final answer:
The physical properties of minerals commonly used to identify them are color, hardness, cleavage, crystal form, density, streak, and luster.
Step-by-step explanation:
The physical properties of minerals that are commonly used to identify them in the field or lab include color, hardness, cleavage, crystal form, density, streak, and luster.
Color is the most straightforward observable property, but it is rarely a diagnostic property for most minerals. Hardness is determined by the ability of a mineral to scratch other minerals or be scratched by them, and it is measured on the Mohs scale.
Cleavage is the tendency of a mineral to break along flat, smooth surfaces, and it is described by the number and angle of these surfaces. Crystal form refers to the geometric shape of a mineral's crystals, and it can vary depending on the conditions in which the mineral formed.
Density is the ratio of a mineral's mass to its volume, and it can be used to distinguish between minerals with similar appearances. Streak is the color of a mineral's powdered form, which can differ from its external color. Luster refers to the way light interacts with the surface of a mineral, and it can be described as metallic, non-metallic, vitreous, pearly, etc.