Minerals & Their Properties

Organic & Inorganic Substances Chemists divide Earth’s substances into these two major categories Organic substances – contain large amounts of carbon and hydrogen joined together (products of living things) Inorganic – do NOT contain carbon and hydrogen joined in that way

Minerals Inorganic solids that occur naturally There are 4 Features of Minerals Occur naturally Inorganic Solid Have a crystalline structure Most minerals are made of compounds of several different elements. A mineral made of only one element is called a native element. (gold and silver)

Classifying Minerals Silicate Minerals Nonsilicate Minerals Contain silicon and oxygen Make up 90% of Earth’s crust Examples: mica, quartz, and feldspar Nonsilicate Minerals Do NOT contain silicon and oxygen Examples: copper, calcite, fluorite, gypsum

Identifying Minerals Minerals can be identified by their physical properties. Color (not the best way to identify a mineral) Luster The way the surface of the mineral reflects light Place luster table here

Crystalline Structure The regular pattern of the atoms in a mineral Place crystalline structure table here The way the crystals form and are arranged causes some minerals to break more easily in one direction or another. Fracture If the mineral breaks irregularly Cleavage When a mineral breaks regularly along a flat surface

Streak Hardness the color of a mineral in its powder form It is not affected by air or water If you rub a mineral across a porcelain tile (or streak plate) it will leave a stripe of color Hardness Each mineral has a distinct hardness that ranges from very soft to very hard Fredrich Mohs developed a hardness scale based on ten relatively common minerals Place Mohs’ Hardness Scale here

Density Other Properties The amount of matter in a given space Density is found by dividing mass by volume (D=m/v) Measured in grams per cubic centimeter (g/cm3) Other Properties Chemical reactions Fluorescence (glow) Magnetism Conductivity (electricity can flow through it)