CGminrlsMINERAL IDENTIFICATIONDefine mineral:1. Naturally occurring2. inorganic *(mineraloid)3. definite crystalline shape (crystal classes)4. well defined chemical composition (within limits)5. Distinct physical propertiesPhysical PropertiesI. LusterMetallic or Non-metallicsilvery (Galena #5) glassybrassy pearlygolden soapy adamintineearthy*magnet test--Magnetite #2II. Streaka. red brown (Hematite #3)b. yellow brown (Limonite #4 or Goethite)c. black--grey black (Pyrite #7 or Chalcopyrite #8)III. HardnessTwo Girls Came From Africa Feeling Quite Tipsy Carrying Diamonds1 Talc (#27)2 Gypsum (#12) (Fingernail 2.5)3 Calcite (#11)4 Fluorite (#14)5 Apatite (knife or nail)(Glass Plate 5.5)6 Feldspar (#16, #17)7 Quartz (18)8 Topaz9 Corundum-sapphire, ruby 10 DiamondFeldspar (60% of crust of earth)1. Plagioclase (17)2. Orthoclase (16)striations or record groovesCGminrlsdiscontinuous wavy linesIV. Cleavage-Tendency of a mineral to break along planes of weakness (look for setsof parallel lines)1. one direction--basale.g. muscouite #20 biotite #212. two directionsa. at right angles (prismatic) Feldsparsb. not at right anglesFeldspars Hornblende #253. Three directionsa. all at right anglescubice.g. halite (#13)galena (#5)b. Rhombohedrale.g. Calcite (#11) fizzes in HCL4. Four way=Octohedral (fluorite #14)5. 6 way=dodecahedralsphalerite (#1)6. Fracturerandom breaksCGminrlsQuartz- concoidal fractureV. Specific GravitySpecific gravity = Weight in air / weight in air - weight in waterVI. TasteVII. Acid test (HCl)VIII. Diaphaneity (ability to transmit light)Transparent, Translucent, opaqueIX. TenacityBrittle, malleable,