1. Physical Science Rocks and Minerals

2. Rocks Igneous rocks – Formed by the cooling and crystallization of hot molten rock called magma Igneous means – formed by fire 95% of the earth crust are igneous rocks examples include basalt and granite From yahoo images

3. Rocks Sedimentary rocks – Formed by weatherd material carried by water, wind or ice. Most common rock in the upper part of the earth’s crust They cover 2/3 of earths surface. Examples include sandstone, shale and limestone From yahoo images

4. Rocks Metamorphic rocks – Formed from pre-existing rocks that are transformed under high temperature and pressure. Metamorphic means – changed in form Examples include marble, slate and diamond From yahoo images

5. Minerals Minerals – The building blocks of rocks. Minerals are naturally formed, generally inorganic crystalline solid composed of an ordered array of atoms having a specific composition. Minerals differ from one another in their combination and proportion of elements and internal arrangement of atoms.

6. Classifying Minerals Crystal form – shape of crystal structure.

7. Classifying Minerals Crystal form – shape of crystal structure.

8. Classifying Minerals Polymorph – mineral composed of the same atom but have different crystal structure.

9. Classifying Minerals Mohs Hardness Scale Hardness is measured on the Mohs Scale, identified numerically hardness of by standard minerals, from 1 (softest) to 10 (hardest): 1.Talc 2.Gypsum 3.Clacite 4.Fluorite 5.Apatite 6.Orthoclase 7.Quartz 8.Topaz 9.Corundum 10.Diamond A mineral of a given hardenss will scratch a mineral of a lower number. With a systematic approach, you can use minerals of known hardness to determine the relative hardness of any other mineral.

10. Classifying Minerals Cleavage – tendency of a mineral to break along planes of weakness. Fracture – break that is not along the lines of a cleavage plane From yahoo images

11. Classifying Minerals Luster – appearance of its surface as it reflects light Luster is independent of color From yahoo images

12. Classifying Luster of Minerals Adamantine - very gemmy crystals Dull - just a non-reflective surface of any kind Earthy - the look of dirt or dried mud Fibrous - the look of fibers Greasy - the look of grease Gumdrop - the look a sucked on hard candy Metallic - the look of metals Pearly - the look of a pearl Pitchy - the look of tar Resinous - the look of resins such as dried glue or chewing gum Silky - the look of silk, similar to fibrous but more compact Submetallic - a poor metallic luster, opaque but reflecting little light Vitreous - the most common luster, it simply means the look of glass Waxy - the look of wax

13. Classifying Minerals Color – is usually a poor way to judge minerals – the same mineral may exhibit a variety of colors Streak – color or mineral in its powder form. Usually obtained by rubbing across a porcelain plate. From yahoo images

14. Classifying Minerals Specific Gravity – Density like measurement based on a comparison with the density of water. From yahoo images

15. Classifying Minerals Chemical properties – fiz test – add HCl to carbonates and it will fizz

16. Makeup of Rocks and Minerals 118 know elements 88 are naturally occurring These combine to make 3400 different minerals About two dozen minerals are abundant These are made from 8 elements

17. Makeup of Rocks and Minerals

18. These 8 elements make up 98 % of the mass of the crust Half of this mass is due to O alone These minerals are broken into groups – silicates oxides & carbonates sulfides & sulfates

19. Building blocks of rock forming minerals Silicates – silicon with oxygen – SiO4

20. Building blocks of rock forming minerals Silicates – silicon with oxygen – SiO4

21. Oxides and Carbonates Oxides – metals combined with oxygen Iron (hematite-magnetite) chromium (chromitite) manganese (pyrolusite) tin (cassiterite) uraninum (uraninite) Most metals come from these ores Hemetite From yahoo images

22. Oxides and Carbonates Carbonates – minerals composed of carbonate ion CO3 Calcite – calcium carbonate CaCO3 Dolomite – calcium and magnesium carbonate CaMg(CO3)2 These two make up limestone calcite From yahoo images

23. Sulfides and Sulfates minerals composed of sulfur S and Sulfate SO 4 2- Pyrite – fools gold FeS2 Gypsum – calcium sulfate CaSO4 pyrite From yahoo images