Minerals Mineral Periodic Table Atomic Structure ATOM FEATURES Shells

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Minerals Mineral Periodic Table Atomic Structure ATOM FEATURES Shells Mineral Periodic table • Naturally occurring • Inorganic Minerals •Solid • Regularly repeating internal arrangement of atoms • Definite chemical composition Rocks may be composed of minerals and/or other material Atomic structure ATOM FEATURES Shells of electrons • Nucleus contains both protons and neutrons • Each atom of an element has the same number of protons in the nucleus • Different atoms of the same element may have different numbers of neutrons in the nucleus • These differing-neutron atoms are called isotopes ELECTRON FEATURES Periodic table PERIODIC TABLE • Arranged from lowest atomic number to • Electrons occur in a cloud around nucleus highest, from left to right, from top to bottom • More likely to occur at certain distances and with a certain amount of energy than • Each row corresponds to an energy shell in other places—the energy shells • Each column contains elements with similar properties, which repeat on a • Inner shells fill before outer shells are regular (or periodic) basis created • These similar properties are a result of the • Full shells more stable than partial shells same number of electrons in the outermost shell 1 IMPORTANT MINERAL Ionic bonding Quartz crystals PROPERTIES • CRYSTAL FORM •LUSTER • COLOR • Result of stability of filled outer shells of • STREAK electrons • HARDNESS • Sodium apt to lose its lone outer electron • Chlorine apt to fill its nearly-full outer shell Pyrite crystals Olivine crystal Fluorite crystals Realgar crystals beryl Nonsilicate—bornite copper ore 2 IMPORTANT MINERAL Cleavage—muscovite Cleavage—fluorite, halite, calcite PROPERTIES • CLEAVAGE • FRACTURE • SPECIFIC GRAVITY • “OTHER” PROPERTIES – TASTE, MAGNETISM, SMELL – FIZZ IN Hydrochloric ACID • DILUTE, HEATED, IF MINERAL IS POWDERED – DOUBLE REFRACTION Fibrous fracture—asbesoform Conchoidal fracture—quartz Galena cleavage mineral Elemental Abundance in Crust Silicate Structure Silica tetrahedron 3 Hornblende Potassium Feldspar Plagioclase Copper Calcite Halite Gypsum The rock cycle Igneous Rocks • Cool from magma • Magma is a mixture of molten rock, solid crystals and dissolved gases • Magma is predominantly silica compounds 4 Norman Levi Bowen’s lab--1910 Bowen’s Reaction Series Bowen • Experiments of melting • Cooling silicate melt igneous rocks • At certain temperature, a particular set of • Discovered minerals minerals will crystallize melt in a distinct and • These will change into different minerals if regular order they remain in contact with magma during • Hypothesized will cooling phase crystallize in opposite order http://vgp.agu.org/bowen_paper/bowen_paper.html http://vgp.agu.org/bowen_paper/bowen_paper.html Bowen’ Reaction Series Bowen’s Reaction Series Sedimentary rock outcrops • At certain temperature, a particular set of minerals will crystallize • Those are the ones present if there is no more magma to solidify • May be removed from remaining magma, so they don’t react with it Sediment deposition Sedimentary rock Sedimentary classification 5 sandstone White cliffs of Dover fossils Dessication cracks Ripple marks Before deformation Granite and gneiss Slate 6 Marble Folded rock Metamorphic deformation • http://www.carrieresducharme.com/interest.htm Convergent plate boundary Oceanic basin tectonics Fold in metamorphic rock • http://my.execpc.com/~acmelasr/mountains/geogramsnf.html • http://my.execpc.com/~acmelasr/mountains/geogramsnf.html Passive continent-to-ocean lithosphere transition • http://www.odp.usyd.edu.au/odp_CD/slope/slindex2.html 7.
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