Mineral characteristics

Warm-up What do you think are the characteristics that determines if a substance is a mineral?

Minerals In order to be classified as a mineral, a substance must meet all of the characteristics Naturally occurring Inorganic Crystalline structure Solid at room temp Specific chemical composition

Naturally Occurring and Inorganic Naturally occurring = not manmade, happens in nature Inorganic = not made by any living thing. Not alive, and never was alive

Crystalline Structure Atoms in the mineral are arranged in a geometric pattern This is called a crystal Size of crystal depends on heat, time to cool, and space to grow in

Specific Composition Every mineral has a chemical composition that is unique to that mineral May vary within a small range based on conditions formed and impurities present

Solid at room temperature This is mostly to exclude water

Color Not the most accurate

Luster The way light interacts with the surface of a crystal, rock, or mineral Typically divided into metallic and non-metallic

Streak the color of the powder produced when it is dragged across an un-weathered surface (typically a ceramic plate)

The ease with which the surface of a mineral can be scratched

Specific Gravity Similar to the Density of a mineral Weight of a mineral compared to the weight of an equal mass of water

Cleavage The tendency of a mineral to break along flat planar surfaces as determined by the structure of its crystal lattice Fracture The way a mineral breaks other than along a cleavage plane.

Exit Ticket What do you think is the most reliable way to identify a mineral? What about the least?