1
A measure of a material's resistance to scratching or abrasion.
2
The way a mineral breaks other than along its cleavage planes.
3
The color of a mineral's powder when scratched on a porcelain plate.
4
The mass per unit volume of a substance, often affecting its weight.
5
The tendency of a mineral to break along flat, even surfaces.
6
The way the mineral reflects light
7
The appearance of a mineral as perceived by the human eye
