Minerals Bauxite (Al(OH)3nH20) Chalcopyrite (CuFeS2) Gold (Au)
Beverage cansElectrical WiresJewelry; Cell phoneUse of minerals
Gold (Au) Graphite (C) Diamond (C) Chromite (FeCr204) Ruby Jewelry;
Cell phoneCircuitryLead PencilDentists drillChrome platingLasers
Quartz (SiO2) Gypsum (CaSO4) Sulfur (S)Glass; Watch
componentPlaster; Taho?Sulfa drugs, Foot powderUse of minerals
Sulfur (S) Galena (PbS) Calcite (CaCO3) Fluorite (CaF2) Silver (Ag)
Sulfa drugs, Foot powderLead plating (x-rays)CementFlux in steel
makingPhotographic filmUse of minerals Practically every
manufactured product is derived from a mineral! Definition of a
mineral1. Naturally occurring2. Inorganic3. Solid 3. Solid4.
Ordered internal structure5. Definite chemical composition (may
vary only very slightly)Naturally occurring Should not be
synthesized Synthetic diamond Ceramics synthesized by chemists and
engineersInorganic Should not have been produced by an organism
Skeletons of Skeletons of animals Shells of molluscs Whewellite
(kidney stones)Solid Liquids are not allowed Mercury (Hg) Mercury
(Hg) Ice is a mineral but liquid water is notOrdered internal
structure Atoms comprising the mineral are arranged in an ordered
fashion Glass does not have any ordered structureDefinite chemical
composition Can vary only slightly e.g. Olivine Fe2SiO4 Mg2SiO4The
ions Fe+2and Mg+2can substitute each other at specific lattice
points Mg2SiO4lattice pointsDefinite chemical compositionCan bring
about the different varieties in color of a mineralMinerals In the
strict sense should satisfy the 5 parts of the definition If some
are not satisfied then they are called If some are not satisfied
then they are called mineraloidsBasic structure of atomTypes of
bondsPrimary bonding forces IonicSecondary bonding forces Ionic
Covalent Metallic Van der Waals Hydrogen bondingIonic bondElectrons
are transferred to form a bondCovalent bondingElectrons are shared
to form a bondPhysical propertieseach mineral is characterized by a
unique set of physical properties1. Crystal form2. Luster3. Color4.
Streak5. Hardness6. Cleavage7. Fracture8. Specific
GravityOthersCrystal form External expression of a mineral that
reflects the ordered internal structure of a mineral structure of a
mineral Cubic Octahedron Rhombic Hexagonal DodecahedronLuster The
appearance or quality of light reflected from the surface of a
mineral surface of a mineral Adamantine Glassy Pearly Greasy
MetallicColor A phenomenon of light by which otherwise identical
objects may beobjects may be differentiated Red Blue Green
YellowStreak The color of a mineral in powdered form Blue Green
Yellow RedHardness1. Talc2. Gypsum3. Calcite4. Fluorite A minerals
resistance to scratching and abrasion4. Fluorite5. Apatite6.
Orthoclase7. Quartz8. Topaz9. Corundum (Ruby)10. DiamondCleavageThe
tendency of a mineral to break along weak planes ofweak planes of
bondingFracture Irregular breaking of a mineral Conchoidal fracture
Splintery fractureSpecific gravity The ratio between the weight of
a mineral and an equal volume of water of waterOther physical
properties Magnetism Fluorescence Double refraction Double
refractionTypes of Minerals 4000 have been named and about 40 to 50
are being named each year No more than a No more than a dozen are
commonMineral Groups Silicates (SiO2, Mg2SiO4) Oxides (Fe2O3, Fe3O
, Al O ) Carbonates(CaCO3,) Native elements(Au, Ag) Oxides (Fe2O3,
Fe3O4, Al2O3) Sulfides (FeS2, ZnS) Sulfates (CaSO4, BaSO4) Native
elements(Au, Ag) Halides (NaCl, CaF2) Hydroxides
PhosphatesAbundance of elements in the Earths crust Oxygen Silicon
Aluminum 46.6 % 27.7 % 8.1 % Aluminum Iron Calcium Sodium Potassium
Magnesium 8.1 % 5.0 % 3.6 % 2.8 % 2.6 % 2.1 %Total =98.3Silicates
Most abundant minerals on earth are silicates Building block is the
Building block is the silicon tetrahedron SiO4-4Silicates
Tetrahedrons can link Polymerization the linking of silicon
tetrahedrons tetrahedronsIgneous rocksIgneous rock Definition: Rock
formed from the crystallization of magma Composed of aggregates of
interlocking Composed of aggregates of interlocking crystalline
mineralsComposition of magma Dominantly ions of Silicon tetrahedra
(SiO4-4) and cations (e.g. Fe+2, Fe+3, Mg+2) moving about in a hot
liquid medium. moving about in a hot liquid medium.Composition of
igneous rock Dominantly silicate minerals mineralsTypes of Igneous
rocks Extrusive (volcanic rock) Intrusive (plutonic rock)Igneous
textures Texture a term used to describe the overall appearance of
the rock based on the size, shape, and appearance of thesize,
shape, and appearance of the interlocking crystals Texture is
important because it can be used to distinguish between an
intrusive rock and an extrusive rockIgneous textures1. Phaneritic2.
Aphanitic 3. Glassy3. Glassy 4. PorphyriticPhaneritic
Coarse-grained texture with crystals large enough to be seen by the
nakedseen by the naked eye (> 1 mm).Aphanitic Fine-grained
texture with crystals not large enough to be seen by the nakedseen
by the naked eye (< 1 mm)Glassy No crystals (minerals) are
formed Unordered ionsPorphyritic Coarse-grained crystals inset in a
finer-grained matrixFactors affecting size of crystals Rate of
cooling Slowrate of cooling large crystals crystals Fast rate of
cooling small crystals Very fast rate of cooling
glassPorphyriticQ:Where did this porphyritic igneous rock
form?A:First at depths of ~10 km from the surface and then was
extruded along with the earlier formed minerals.PorphyriticQ:Where
did this porphyritic igneous rock form?A:First at depths of ~10-20
km from the surface and was emplaced as an intrusive a few km below
the surface of the earth.Heat source why rocks melt1. Geothermal
gradient2. Decay of radioactive isotopesWhere rocks melt Below
oceanic ridges At subduction zonesWhat are rocks that melt Oceanic
crust (Basalt) and parts of the upper mantle (Peridotite)
Continental crust (Granite) and parts of the upper mantle
(Peridotite) (Peridotite)Crystallization of melts Bowens reaction
series The relationship between magma and the minerals
crystallizing from it during the formation ofcrystallizing from it
during the formation of igneous rocks N.L. Bowen Some ions prefer
to crystallize earlier than others There occurs selectivedepletion
of ions in thedepletion of ions in the liquid magma (circles,
triangles, and squares represent ions)Bowens reaction
seriesGraniteDioriteBiotiteMuscoviteQuartzNa-rich
plagioclaseRhyoliteLow-temperatureDioriteGabbroPeridotiteOlivinePyroxeneAmphiboleCa-rich
plagioclaseAndesiteBasaltHigh temperature