This document provides information about physical properties of various minerals, including cleavage, luster, hardness, and streak. It lists several common minerals along with their distinguishing physical characteristics. Cleavage is described as the flat surfaces along which minerals may split or break. Luster refers to how the mineral reflects light and can be metallic, non-metallic, or somewhere in between. Hardness is measured on the Mohs scale and indicates a mineral's resistance to scratching. Streak is the color of a mineral's powder or dust.