GEOLOGY 1008 NAME:
EXERCISES 1 & 2 - MINERALS
Step 1: Identify the properties of the minerals using the instructions provided in the lab book Chapter 1.
Step 2: Determine each mineral's identity using the properties and the charts provided in the lab book Chapter 2. (note: All of the minerals listed on the chart are present except chromite, chalcopyrite, goethite, serpentine, apatite, barite, tourmaline, topaz, beryl, kyanite, sillimanite, epidote, and opal. Some of the minerals appear more than once on the tables, but each appears only once as an answer). NOTE: Sometimes one mineral can occur in several different forms, the samples in each box are of one mineral type, if you think some of the minerals have been mixed up, tell Mrs. Johnson, do not switch them yourself.
Step 3: Answer the questions at the end of the chart.
| # |
MINERAL NAME (use the tables on p 25-30) | ||||||
|---|---|---|---|---|---|---|---|
|
luster (p 2-3) |
color
(p 2) |
hardness (# value, p 3-4, table & text) |
streak
(p 4-5) |
cleavage (p 5-8) |
other observations |
||
| 1
|
non-metallic (glassy/ vitreous) | clear, grey, light brown | 2 - 3 | --- | 1 direction, sheets | ||
| 2
|
|
||||||
| 3
|
non-metallic | white | 6 - 6.5 | --- | 2 directions at 90o | some striations visible on cleavage plane | plagioclase feldspar |
| 4
|
|||||||
| 5
|
|
|
none | grainy | |||
| 6
|
non-metallic | various | 7 | --- | no cleavage, conchoidal fracture | one sample has clear multi-sided crystals | quartz |
| 7
|
|
|
2 directions at 60o and 120o | ||||
| 8
|
non-metallic | black | 6 | black | 2 directions at 90o | augite (pyroxene) | |
| 9
|
3 directions, rhombic | fizzes with HCl | |||||
| 10
|
chalky, sticks to tongue | ||||||
| 11
|
salty | ||||||
| 12
|
some large, multi-sided crystals, some fibrous pieces | ||||||
| 13
|
|||||||
| 14
|
1 direction, platy, scaly | chlorite | |||||
| 15
|
|
soapy feel | |||||
| 16
|
non-metallic | red | 7 - 7.5 | --- | no cleavage, conchoidal fracture | garnet | |
| 17
|
non-metallic | red-brown | 7 - 7.5 | --- | none seen | prismatic crystals - crossed | |
| 18
|
metallic | silver, grey | 2.5 | black, grey | 3 directions, cubic | heavy | |
| 19
|
6 directions | ||||||
| 20
|
non-metallic | purple, yellow | 4 | white | 4 directions | ||
| 21
|
none | fool's gold, cubic and pyritohedral crystals visible using hand lens, striations visible on crystal faces | |||||
| 22
|
none | greasy feel | |||||
| 23
|
none | grainy | |||||
| 24
|
metallic or non-metallic | black | 6 | --- | none | magnetic, heavy | |
| 25
|
metallic or
non-metallic |
grey, brown, orange | 5 - 6 | brown | none | rusty | |
| 26
|
metallic | copper, orange | 2.5 to 3 | copper red | none | heavy | |
| 27
|
non-metallic | blue/green | 3.5 to 4 | blue/green | none | two minerals | azurite & malachite |
| 28
|
non-metallic | yellow | 1.5 to 2.5 | yellow | none | light weight | |
| 29
|
non-metallic | reddish brown, brown | 1 to 6 | faint red-brown | none | mass of pea-shaped structures | |
| 30
|
non-metallic | blown, blue, grey | 9 | none | none | six-sided crystals | |
Why are we looking at these minerals?
Questions:
Mineral 10 is a type of clay, a common product of the chemical alteration of some of the minerals 1 to 9. From which minerals would you suspect it derives? (Hint: compare the chemical formulas on p. 30-31)
Which of the minerals you identified above fall into the following groups? (p.30 & 31)
Silicates:
Oxides:
Native elements:
Sulfides:
Carbonates:
Which minerals identified may be used as gemstones? (text page 55)