Elements/atoms:  basic building blocks of all matter, organized by size and # of electrons
     common atoms in solid Earth: O (80%!!!), Si, Ca, Al, Fe, Mg, K, Na, S, C, Pb, F, Cl

Mineral:  solid (orderly pattern of atoms), natural, not organic, ± fixed composition, neutral
      minerals = crystals:  ex: quartz, diamond, ruby, mica, turquoise, garnet, etc.
     minerals defined by how atoms/elements are arranged in space into a solid form
      shape and form of minerals reflects how the atoms are bonded together in space
          bonding : covalent bonds, ionic bonds, weak Van der Wahls bonds, etc.

How minerals form and grow:  1: minerals grow from liquid magma (igneous minerals)
     2: minerals grow from ions dissolved in water or air (usually from sea water, hot water)
     3: direct transformation from one solid mineral to another; graphite to diamond, etc.

Mineral Properties:  physical properties of minerals: how to tell minerals apart
    color, streak (color of powdered mineral), luster (shininess), opacity (transparency)
      hardness (scratchability), Moh's hardness scale: Talc-G-C-F-A-F-Q-T-C-Diamond!
      natural form/shape of free growing mineral, habit, cleavage (how mineral breaks)
      magnetism, taste, density ("specific gravity", the heft test), fizz test with acid

Gangs/Groups of Minerals: based on similar chemical composition and properties
     silicates-----------silicon bonded to oxygen------see below (quartz, feldspar, etc.)
     oxides-------------oxygen without silicon---------magnetite, hematite (rust)
     salts/halides----halogen (F, Cl) dominant------rock salt/halite, sylvite, fluorite
     sulfides-----------sulfur (S) dominant-------------galena, pyrite (fool's gold)
     carbonates-------carbonate molecule CO3-2 -----calcite, dolomite
     sulphates--------sulphate molecule SO3-2 -------gypsum, anhydrite
     pure metals-----one metal element---------------gold the mineral, copper the mineral
     miscellaneous-------------------------------------------graphite, diamond

Silicates: most common gang.  silicon (Si) bonded with oxygen (O) in formula (...SiO...)
     feldspar group--sodium (Na), potassium (K) and calcium (Ca) feldspars
          very common in both continental and oceanic crust, absent in mantle
     quartz: very common in continental crust, absent in ocean crust, mantle
     mica group --biotite (black), muscovite (colorless), chlorite, kaolinite, vermiculite
     pyroxene group---Ca-pyroxene (black), Na-pyroxene (green)
     amphibole group---Ca-amphibole (green), Na-amphibole (blue), hornblende (black)

Uses of Minerals and Some Interesting Mineral Factoids
     use minerals to make rocks!!!  rocks are aggregates of minerals stuck together
     minerals are sources of elements, metals and chemicals; antacids, Fe-supplements...
     asbestos: cancer causing mineral group found as insulation in older buildings
     there are clay minerals in your food used as fillers: ice cream, candy bars, etc. etc.
     many gems are FAKES! some are ugly minerals altered to make them gem-like
     diamonds are worth 10 times less than their price!!!  ever try to sell a diamond?
     quartz crystals actually produce electricity when you squeeze them (piezoelectric)
 

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