2. Mineral - A naturally occurring, inorganic, homogeneous solid with a definite chemical composition and an ordered atomic arrangement.
naturally occurring - materials synthesized in laboratory do not count, must be formed by natural processes in wild
inorganic - not formed by organic chemistry (e.g., sugars, etc.)
homogeneous solid - single substance in solid phase which cannot be physically separated into simpler compounds
definite chemical composition - composition can be represented as chemical formula (e.g., NaCl), although variation in exact composition is possible (e.g., (Mg, Fe)2SiO4 ) [range in color, hardness, specific gravity]
ordered atomic arrangement – repeating structure at the atomic level, which expresses as symmetry in large specimens, i.e., crystalline structure.

3. COLOR Quartz SiO2 Hardness = 7 Rose Quartz Smokey Citrine Amethyst
Carnelian
Onyx
Jasper

4. CRYSTAL FORM
Figure 3.4

5. Good for metallic and opaque minerals, softer than the streakplate
Figure 3.7
Good for metallic and opaque minerals, softer than the streakplate

6. HARDNESS
Figure 3.9

7. HARDNESS
Figure 3.8

8. metallic Luster - quality of light reflected from mineral surface
pyrite
metallic
silver
gold

9. non-metallic vitreous (glassy) pearly resinous Luster
quality of light reflected from mineral surface
non-metallic
Some minerals may be listed in both metallic and non-metallic, or in the incorrect table, i.e., limonite
vitreous (glassy)
pearly
resinous

10. CLEAVAGE Cleavage: Breaks along planes of weakness
See the way light reflects back at you (I cannot see this for you). Rotate the mineral to “find” reflective surfaces. When you find a cleavage plane, rotate
Figure 3.10

11. CLEAVAGE
Figure 3.10a

12. CLEAVAGE
Figure 3.10b

13. CLEAVAGE
Figure 3.10c

14. CLEAVAGE
Figure 3.10d

15. Figure 3.12

16. NO CLEAVAGE - FRACTURE
Figure 3.12a

17. CLEAVAGE – 1 PLANE, EXCELLENT
Figure 3.12b

18. Figure 3.13

19. CLEAVAGE – 2 PLANES, GOOD
Figure 3.12c

20. Figure 3.15

21. Figure 3.12d

22. Figure 3.14

23. Figure 3.14a

24. Figure 3.14b

25. CLEAVAGE – 3 PLANES, GOOD
Figure 3.12e

26. CLEAVAGE – 3 PLANES, GOOD
Figure 3.12f

27. CLEAVAGE – 4 PLANES, GOOD
Figure 3.12g

28. CLEAVAGE – 6 PLANES, GOOD
Figure 3.12h

29. EFFERVESCENCE
Minerals like calcite react with weak acid, dissolving the mineral and producing lots of bubbles (effervescence)
Calcite: CaCO3
HCl + CaCO3 > H2O + Cl- + Ca+ + CO2
Dolomite: CaMg(CO3)2

30. SPECIFIC GRAVITY Mass / Volume (gm/cm3) Orthorhombic Carbonates
All minerals have same structure, only cation differs
Mineral Formula Cation g/cm3
Aragonite CaCO
Strontianite SrCO
Witherite BaCO
Cerrusite PbCO
Figure 3.17

31. PAGE 90
Figure 3.18

32. PAGE 91
Figure 3.18

33. PAGE 93
Figure 3.21a

34. UnFigure Pg101_1

35. ONE QUARTZ CRYSTAL, DOUBLY TERMINATED
UnFigure Pg101_1b

36. MULTIPLE CRYSTALS: Galena, Flourite
UnFigure Pg101_1c

37. Look at minerals: Galena, Olivine
IGNEOUS ROCK, Granite, with quartz, potassium feldspar, plagioclase, biotite
Randomly Oriented.
Look at minerals: Galena, Olivine
UnFigure Pg101_1d