3. 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.
5. TABLE SALT CRYSTALS -
CUBIC
THE CRYSTAL SHAPE IS A
RESULT OF THE WAY THE
ATOMS ARE ARRANGED IN THE
CRYSTAL
6. 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.
7. 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
8. 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
9. 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.
10. 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.
11. QUARTZ (SiO2 - 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.
12. 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.
13. 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.
14. VERY PURE QUARTZ CAN BE GROWN IN THE
LABORATORY.
THIS QUARTZ IS USED IN THE ELECTRONICS
INDUSTRY.
15. 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
16. 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.
17. MICA IS A SILICATE MINERAL, MEANING IT
CONTAINS SiO4. 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.
19. 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.
20. 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.
21. 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.
