Section #: 4.1
What is a mineral?
Practice Test
1.
What is the correct atomic composition of quartz?
a.
two silica atoms and one iron atom
b.
four atoms of silica and oxygen each
c.
two silica atoms
d.
two oxygen atoms and one silica atom
Hint
2.
According to the table, what is a characteristic of metallic minerals?
Table 2
Minerals with Metallic Luster
Mineral
(Formula)
Color
Streak
Hardness
Specific Gravity
Crystal System
Breakage pattern
Uses and Other Properties
Bornite
(Cu
5
FeS
2)
bronze, tarnishes to dark blue purple
gray-black
3
4.9-5.4
tetragonal
uneven fracture
source of copper
called "peacock ore" Because of the purple shine when it tarnishes
Chalcopyrite
(CuFeS
2
)
brassy to golden yellow
greenish black
3.5-4
4.2
tetragonal
uneven fracture
main ore of copper
Chromite
(FeCr
2
O
4
)
black or Brown
brown to Black
5.5
4.6
cubic
irregular fracture
ore of chromium, stainless steel, metallurgical bricks
Copper
(Cu)
copper red
copper red
3
8.5 -9
cubic
hackly
coins, pipes, gutters, wire, cooking utensils, jewelry, decorative plaques; malleable and ductile
Galena (PbS)
gray
gray to black
2.5
7.5
cubic
cubic cleavage perfect
source of lead, used in pipes, shields for X-rays, fishing equipment sinkers
Gold
(Au)
pale to golden yellow
yellow
2.5-3
19.3
cubic
hackly
jewelry, money, gold leaf, filling for teeth, medicines, does not tarnish
Graphite
(C)
black to gray
black to gray
1-2
2.3
hexagonal
basal cleavage (scales)
pencil lead, lubricants for locks, rods to control some small nuclear reactions, battery poles
Hematite
(Specular)
(fe
2
O
3
)
Black or reddish brown
red or reddish brown
6
5.3
hexagonal
irregular fracture
source of iron; roasted ina blast furnace, converted into pig iron, made into steel
Magnetite
(fe
3
O
4
)
black
black
6
5.2
cubic
conchodial fracture
source of iron, naturally magnetic, called lodestone
Pyrite
(FeS
2
)
light, brassy yellow
greenish black
6.5
5.0
cubic
uneven fracture
source of iron, [CDATA["]]fool's gold,[CDATA["]] alters to limonite
Pyrrhotite
(Fe
1-x
S
)*
*contains one less atom of Fe than S
bronze
gray-black
4
4.6
hexagonal
uneven fracture
an ore of iron and sulfur; may be magnetic
Silver(Ag)
silvery white, tarnishes to black
light gray to silver
2.5
10-12
cubic
hackly
coins, filling for teeth, jewelry, silver plate, wires; malleable and ductile
a.
colorless streak
b.
low hardness value
c.
no crystalline structure
d.
gray, green, brown, or red streak
Hint
3.
Which is a mineral?
a.
coal
b.
amber
c.
sugar
d.
salt
Hint
4.
A(n) __________ is a solid in which the atoms are arranged in repeating patterns.
a.
atom
b.
crystal
c.
rock
d.
magma
Hint
5.
When magma cools quickly, __________ crystals form, and when it cools slowly, __________ crystals form.
a.
large, large
b.
small, large
c.
shiny, dull
d.
broken, crystals
Hint
6.
What is the most abundant element in Earth's crust?
a.
potassium
b.
silica
c.
iron
d.
oxygen
Hint
7.
Which crystal shown in the figure is hexagonal?
a.
1
b.
2
c.
3
d.
none are hexagonal
Hint
8.
What is the molten material under Earth's crust called?
a.
magma
b.
solution
c.
basalt
d.
minerals
Hint
9.
Which crystal shown in the figure is the type of crystal found in pyrite?
a.
1
b.
2
c.
3
d.
none are found in pyrite
Hint
10.
How do crystals of salt form?
a.
from solution
b.
from magma
c.
in glacial ice
d.
inside caves
Hint
11.
A crystal is found with monoclinic structure. What element shown in the figure is this crystal most like structurally?
a.
pyrite
b.
topaz
c.
gypsum
d.
feldspar
Hint
12.
Which is not a characteristic of a mineral?
a.
definite crystal structure
b.
organic solid
c.
specific chemical composition
d.
naturally occurring
Hint
13.
What are the common minerals called?
a.
rock-forming minerals
b.
crystal minerals
c.
igneous minerals
d.
abundant minerals
Hint
14.
What is an example of an oxide?
a.
anhydrite
b.
calcite
c.
sulfur
d.
magnetite
Hint
