I’VE NEVER LET MY SCHOOL INTERFERE WITH MY EDUCATION. - Mark Twain -

MINERALS

MINERALS ARE INORGANIC SOLIDS OF GEOLOGICAL ORIGIN AND OF A GIVEN COMPOSITION. THEY ARE CRYSTALLINE, BECAUSE THE ATOMS ARE ARRANGED IN A REPEATING PATTERN. THIS PATTERN IS CALLED THE CRYSTAL LATTICE, AND THIS IS WHAT GIVES THE MINERAL ITS PARTICULAR SHAPE. MINERALS ARE THE BUILDING BLOCKS OF ROCKS.

CUBIC TETRAGONALORTHORHOMBIC HEXAGONAL MONOCLINICTRICLINIC

TABLE SALT CRYSTALS - CUBIC THE CRYSTAL SHAPE IS A RESULT OF THE WAY THE ATOMS ARE ARRANGED IN THE CRYSTAL

CRYSTAL STRUCTURE IS A USEFUL PROPERTY IN IDENTIFYING A MINERAL. HOWEVER, IN NATURE, NICE CRYSTALS ONLY FORM IF THE CRYSTAL HAS ROOM TO GROW. IF THE CRYSTALS OF THE MINERAL ARE GROWING IN A RESTRICTED AREA, THEY CAN BE ALL INGROWN.

THERE ARE OTHER PROPERTIES THAT CAN BE USED IN IDENTIFYING MINERALS: 1.COLOR 2.LUSTER - THE WAY THE LIGHT REFLECTS OFF THE SURFACE 3.STREAK - THE COLOR OF A MINERAL WHEN IT IS POWDERED 4.HARDNESS - THERE IS A HARDNESS SCALE THAT CAN BE USED TO COMPARE MINERALS 5.CLEAVAGE OR FRACTURE - HOW A MINERAL BREAKS 6.CHEMICAL ANALYSIS - WHAT ELEMENTS ARE PRESENT

Mohs scale number (mineral example) 1 (Talc) 2 (Gypsum) 3 (Calcite) 4 (Fluorite) 5 (Apatite) 6 (Orthoclase Feldspar) 7 (Quartz) 8 (Topaz) 9 (Corundum) 10 (Diamond) Hardness of other common objects Fingernail: 2.5 Copper penny: 3 Glass: 5.5

THERE ARE TWO MAIN WAYS MINERALS CAN FORM: 1.WHEN MAGMA OR LAVA (MOLTEN ROCK) STARTS TO COOL, ATOMS OF DIFFERENT ELEMENTS CAN BOND TOGETHER INTO MINERAL CRYSTALS. 2.WHEN WATER THAT CONTAINS DISSOLVED ELEMENTS IN IT EVAPORATES, MINERAL CRYSTALS CAN FORM.

HOW MANY DIFFERENT MINERALS EXIST? THERE ARE ABOUT 2000 DIFFERENT MINERALS, BUT THERE ARE 200 COMMON MINERALS THAT MAKE UP MOST OF THE MINERALS. THE MOST COMMON CLASS OF MINERALS ARE THE SILICATES - MINERALS MADE UP MOSTLY OF SILICON AND OXYGEN WITH POSSIBLY A METAL ALSO PRESENT. EXAMPLES ARE QUARTZ AND FELDSPAR. CARBONATES ARE ALSO COMMON. THESE ARE MADE UP OF CARBON, OXYGEN, AND A METAL. AN EXAMPLE IS CALCITE - CALCIUM CARBONATE.

QUARTZ (SiO 2 - SILICA) IS ONE OF THE MOST COMMON MINERALS. IT IS HEXAGONAL, BUT IN NATURE, YOU DON’T ALWAYS SEE THIS. WHEN MINERALS CRYSTALLIZE IN A CONFINED SPACE, THE CRYSTALS ARE ALL GROWN TOGETHER.

QUARTZ IS VERY RESISTANT TO CHEMICAL OR PHYSICAL WEATHERING. WHEN ROCKS CONTAINING QUARTZ WEATHER, THE GRAINS OF QUARTZ CONCENTRATE IN THE SOIL, IN RIVERS, AND ON BEACHES. THIS IS SAND. SOMETIMES, FELDSPAR, ANOTHER SILICATE MINERAL, WILL BE PRESENT TO ADD A PINK TO TAN COLOR.

QUARTZ CAN CONTAIN IMPURITIES AND BE OTHER COLORS THAN JUST CLEAR. AMETHYST IS PURPLE QUARTZ. ROSE QUARTZ IS PINK. CITRINE IS YELLOW OR ORANGE. MILKY QUARTZ IS WHITE. SMOKY QUARTZ IS BLACK.

VERY PURE QUARTZ CAN BE GROWN IN THE LABORATORY. THIS QUARTZ IS USED IN THE ELECTRONICS INDUSTRY.

THE FELDSPAR GROUP OF MINERALS ARE THE MOST ABUNDANT MINERALS ON EARTH. THIS GROUP INCLUDES 1.CALCIUM ALUMINUM SILICATES 2.POTASSIUM ALUMINUM SILICATES 3.SODIUM ALUMINUM SILICATES

Feldspar: A rock-forming mineral, industrially important in glass and ceramic industries, pottery and enamelware, soaps, abrasives, bond for abrasive wheels, cements and concretes, insulating compositions, fertilizer, poultry grit, tarred roofing materials, and as a sizing (or filler) in textiles and paper.

MICA IS A SILICATE MINERAL, MEANING IT CONTAINS SiO 4. DIFFERENT MICAS CAN ALSO CONTAIN IRON, POTASSIUM, AND ALUMINUM. MICA IS UNUSUAL IN THAT THE SILICATE GROUPS BOND TO FORM SHEETS. IN NATURE, MICA CAN BE FOUND IN LARGE SHEETS OR IN FLAKES. THE SHEETS ARE USED IN THE ELECTRONICS INDUSTRY. MICA DOES NOT CONDUCT ELECTRICITY AND IS HEAT RESISTANT. THE FLAKES ARE USED AS GLITTER IN PAINTS AND COSMETICS AND AS A SEALER AND FILLER.

MICA

CORUNDUM - ALUMINUM OXIDE CORUNDUM IS THE SECOND HARDEST NATURALLY OCCURING MINERAL. IT IS 9 ON THE MHOS HARDNESS SCALE. ONLY DIAMOND IS HARDER. THE RED FORM OF CORUNDUM IS RUBY. OTHER COLORS ARE SAPPHIRE.

NORTH CAROLINA IS THE LEADING PRODUCER OF FLAKE MICA, LITHIUM MINERALS, FELDSPAR, AND PYROPHYLLITE IN THE NATION. PYROPHYLLITE IS USED AS A REFRACTORY AND IN PAINTS AND CERAMICS. IT IS A HIGH ALUMINA MINERAL. THE STATE MINERAL IS EMERALD. THE LARGEST EMERALD FOUND IN NORTH AMERICA WAS FOUND IN NC. IT HAD A WEIGHT OF 1,438 CARATS. THE STATE ROCK IS GRANITE.

NORTH CAROLINA WAS ONCE THE LEADING GOLD PRODUCING STATE IN THE U.S. IN 1788, A 17 POUND NUGGET WAS FOUND IN CABARRAS COUNTY. GOLD WAS MINED IN NC UNTIL 1942.