to make a solution of, as by mixing with a liquid; pass into solution: to dissolve salt in water. to melt; liquefy: to dissolve sugar into syrup. to undo (a tie or bond); break up (a connection, union, etc.). to break up (an assembly or organization); dismiss; disperse.
The Mohs scale of mineral hardness is based on the ability of one natural sample of mineral to scratch another mineral visibly. The samples of matter used by Mohs are all different minerals. Minerals are pure substances found in nature. Rocks are made up of one or more minerals.
Mohs hardness scale was devised in 1812 by Friedrich Mohs and has been the same ever since, making it the oldest standard scale in geology. It is also perhaps the most useful single test for identifying and describing minerals.