Minerals
Natural substance belonging to a group of inorganic (often crystalline) compounds which are found in the earth, that which is not animal or vegetable
A mineralis a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties
Elements as Parts of Minerals
Oxygen, Silicon, Carbon, Sulphur, Phosphorus, Halogens (Flourine, Chlorine, Bromine, Iodine)
Characteristics to Identify Minerals
Color - this varies depending on the chemicals present and is the least informative in identifying a mineral variety
Luster - what the surface looks like in the light
Specific Gravity - how heavy it feels, heft
Crystal Form - shape of crystal, shape the mineral would take if it had room to grow in a cavity, not massive - some minerals have a number of different crystal shapes
Cleavage - pattern when mineral is broken - in planes or conchoidal Fracture
Tenacity - toughness, how cohesive the mineral is, if it falls apart
Hardness - what it can scratch & what scratches it
Transparency - The ability to transmit light. Depending on a number of things, rocks & minerals can also transmit light.