1. 2 - MINERALS Building Blocks of Rocks Matter & Atomic Structure Bonding Minerals –Physical properties of minerals –Major rock-forming mineral families –Silicates - rock-forming SUPER STARS

2. Structure of an Atom Protons +/1 Neutrons 0/1 Electrons -/0

3. Two-dimensional representation of a 12 C atom Fig. 3.1BFig. 3.1B

5. BONDING - 4 kinds  IONIC - electrical charge  COVALENT - sharing  METALLIC - inner shell covalent bond  INTERMOLECULAR - Van der Waal’s

6. IONIC BONDING - electrical

8. Covalent Bonding in Diamond

9. Covalent Bonds in Water

10. Carbon Atoms in Graphite

11. MINERALS - Rock Builders  NATURALLY FORMED  INORGANIC  CRYSTALLINE & SOLID  DIAGNOSTIC CHEMICAL COMPOSITION

13. Galena (PbS) CRYSTALLINE SOLID

14. Atomic Structure of Galena Sulfur Lead DIAGNOSTIC CHEMICAL COMPOSITION

15. Ionic Radii & charge of some geologically important ions allows “ionic substitution” or SOLID SOLUTION

16. WHAT FACTORS DETERMINE WHAT MINERAL WILL FORM?  WHAT ELEMENTS ARE AVAILABLE  ABUNDANCE OF EACH ELEMENT  SIZE & CHARGE OF EACH ELEMENT  ENVIRONMENT - SPACE, PRESSURE, TEMPERATURE

17. Irregular Intergrowth of Quartz

18. Banded Agate

19. Identify Minerals by Their Physical Properties  Crystal Habit  Cleavage & Fracture  * Striations  Hardness  Specific Gravity  Color  Streak  Luster  Acid Test

20. Constancy of Interfacial and Angles in Quartz Crystal Form - Constancy of Interfacial Angles

21. Cleavage

22. Striations: Pyrite (Fool’s Gold) FeS)

24. Brian Skinner Examples MOH’S HARDNESS SCALE

25. The Different Colors of Corundum Ruby Sapphire

26. Streak - color of rock power

27. GALENA (Pb S) - Identified by: crystal habit luster specific gravity hardness

28. Acid Test

29. Average Composition of the Continental Crust Weight PercentVolume Percent Si O O

30. COMMON ROCK-FORMING MINERAL FAMILIES  NATIVE ELEMENTS - GOLD, COPPER  HALIDES - PRECIPITATES  OXIDES - 1 METAL + OXYGEN  SULFIDES - 1 METAL + SULFUR  SULFATES - (SO 4 ) 2-  CARBONATES - (CO 3 ) 2-  SILICATES - SUPER STARS!!!

31. One view of the Silica Tetrahedron

32. More Views of the Silica Tetrahedron

33. Linking Silicate Tetrahedra

34. About Silicates  There are 2 families of silicates:  FERROMAGNESIAN SILICATES - Fe/Mg -> MAFIC MINERALS  NONFERROMAGNESIAN or ALUMINO- SILICATES -> FELSIC MINERALS

36. Olivine: formed from single silica tetrahedra (Mg,Fe) 2 SiO 4

37. Cleavage in the Chain Silicates Pyroxene Amphibole

38. Framework (example: quartz)

39. SHEET SILICATES Clay: a sheet silicate

41. GREEN FELDSPAR

43. Polished Section ~1 cm

44. Thin Section

45. Thin section under ordinary light Magnetite Mica Quartz Feldspar

46. Thin section under polarized light