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And some rin uphill and down dale, Knapping the chucky stones to pieces wi ’ hammers, Like sae mony roadmakers run daft – They say it is to see how the warld was made. - Sir Walter Raleigh Minerals. Lecture 4. Webpage for course (daytime). Webpage for course (nighttime).
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And some rin uphill and down dale,Knapping the chucky stones to pieces wi’ hammers,Like saemonyroadmakers run daft –They say it is to see how the warld was made. - Sir Walter RaleighMinerals Lecture 4 Webpage for course (daytime) Webpage for course (nighttime)
What is a mineral? A naturally occurring inorganic solid made up of an ordered arrangement of ATOMS
Mass (wt.) charge Atoms, three basic parts Protons Neutrons Electrons
nucleus electron cloud Fig. 2.5
Atomic number = Atomic mass number =
Atomic number = number of protons Atomic mass number = number protons and neutrons Example: Carbon (symbol “C”) atomic number = atomic mass number = Therefore, 6 protons, 6 (12-6) neutrons
Electrons are not randomly located Occur in “shells” electrons fill shells in a sequential order
1st shell holds up to 2 electrons2nd shell holds up to 8 electrons3rd shell holds up to 8 electrons
Two rules in Nature: 1. electrons occupy shells in a specific order (inner before outer shells) 2. Outer shell that has electrons in it must be full of electrons
Two rules in Nature: 1. electrons occupy shells in a specific order (inner before outer shells)2. Outer shell that has electrons in it must be full of electrons
Our cast of characters outerelement sym + +/- - # wt. sh. Needs Hydrogen H Helium He Carbon C Oxygen O Sodium Na Chlorine Cl Iron Fe Uranium U
More formulaeCaCO3 (calcite)KAl2(Si3Al)O10(OH)2 (muscovite)Ca3Al2Si3O12 (garnet)
Silicate minerals SiO4 tetrahedra Isolated Olivine Chains Hornblend Sheets Mica Framework Feldspar & Quartz
So, what the atoms are and how to go together determines the characteristics of the mineral: crystal shape hardness cleavage chemical properties etc. etc.