1. Earth & Space Science - Chapter 5 Test Review Guide
The ten most common minerals make up ______ % of the Earth’s crust. 10
2. What do the properties of a mineral result from?
Chemical Composition
3. Define the following:
a. Luster:
Shine or lack of shine; the way a mineral reflects light.
b. Cleavage:
Splits along smooth surfaces.
c. Phosphorescence:
Continues to glow after exposure to UV.

2. d. Streak:
Color of mineral’s powder.
e. Specific Gravity (SpG):
How dense a mineral is compared to water; weight of mineral in air ÷ weight loss of mineral placed in water.
f. Mineral:
Any solid substance which occurs naturally in Earth
What is the most common magnetic mineral?
Magnetite (#22)
What is the most common silicate mineral?
#1 = Feldspar (#6)
#2 = Quartz ( #7 & #60)

3. 6. What is the hardest mineral on the Moh’s scale?
Diamond (Sorry, I BORROWED all of the samples)
What is the softest mineral on the Moh’s scale?
Talc (#8)
What is the specific gravity of a mineral
that weighs 12 grams in air and 10 grams in water?
12 ÷ (12 – 10) = 6
Which mineral is easily identified by the acid test?
Calcite (#2 & #64)
What gas is given off during a positive acid test?
CO2
List examples of silicate minerals.
Feldspar (#6), mica (#11 & 12),
quartz (#7 & 60),
augite (don’t have a sample)

4. 12. Why can’t minerals be identified by color alone?
Minerals exist in a variety of colors.
13. What is a general rule regarding the streak of metals and nonmetals?
The streak of a metal is at least as dark as the specimen.
The streak of a nonmetal is usually lighter, white or colorless.
14. List some characteristics of calcite.
3 cleavages not at 90° angles; reacts with HCl (acid); double refraction in transparent varieties; chief mineral in limestones.
15. What physical property best helps
to identify hornblende?
Fine, parallel lines or striations.

5. 16. Which minerals have one perfect cleavage?
Muscovite (white mica; #12) and
Biotite (black mica; #11)
17. What elements are found in:
a. Feldspars:
Si, O, & a metal;
make up 60% of crust
b. Carbonates:
1 C and 3 O; calcite, dolomite, malachite
c. Nonsilicates:
Can contain C, Au, Fe; example – Fluorite (#4)
d. Silicates:
Silica tetrahedron; 1 Si and 4 O
18. Feldspar and quartz make up ______ of the Earth’s crust.
50%

6. 19. Draw the shape of a quartz crystal. How hard is quartz
19. Draw the shape of a quartz crystal. How hard is quartz on the Mohs Scale? Of what is quartz composed?
7 on Mohs Scale
Tightly bound silica tetrahedra
20. How does the Mohs Scale work?
Scratch an unknown mineral against known minerals or objects of known hardness.
21. List several types of nonmetallic luster.
Pearly, earthy, vitreous, resinous
What is conchoidal fracture?
Shell-like breaks, common in glassy minerals.
Example: Quartz (and the rock, obsidian)
What special property does Iceland Spar have?
Double refraction

7. What is fracture?
The mineral separates along surfaces other than cleavage surfaces.
25. Describe minerals in the amphibole family.
Form long, needle-like crystals;
contain Fe and Mg;
Example: Hornblende (#10)