GEOL 1121L Lab 3: Mineral Identification Quiz Questions and Answers
100% PASS-GSU
1. Which of the following is NOT part of the definition of a mineral?
A. Organic composition
B. Inorganic solid
C. Naturally occurring
D. Ordered internal crystalline structure
Answer: A
Rationale: Minerals must be inorganic; organic substances like coal are not considered
minerals in a geological sense.
2. Which mineral is the softest on the Mohs Hardness Scale?
A. Fluorite
B. Gypsum
C. Calcite
D. Talc
Answer: D
Rationale: Talc is the softest mineral with a Mohs hardness of 1.
3. What is the hardest known mineral on the Mohs Scale?
A. Quartz
B. Diamond
C. Corundum
D. Topaz
Answer: B
Rationale: Diamond is the hardest mineral, rated at 10 on the Mohs scale.
,4. What property refers to the color of a mineral in powdered form?
A. Luster
B. Hardness
C. Cleavage
D. Streak
Answer: D
Rationale: Streak is the color of a mineral’s powder, often more reliable for identification
than the mineral’s external color.
5. Which mineral reacts (effervesces) when a drop of dilute hydrochloric acid is
applied?
A. Calcite
B. Halite
C. Quartz
D. Hematite
Answer: A
Rationale: Calcite is a carbonate mineral that reacts with acid to release carbon dioxide
gas.
6. Which mineral is strongly attracted to a magnet?
A. Magnetite
B. Pyrite
C. Galena
D. Hematite
Answer: A
Rationale: Magnetite is a natural magnet and is strongly attracted to magnetic fields.
, 7. The tendency of a mineral to break along smooth, flat planes of weakness is
called:
A. Hardness
B. Fracture
C. Cleavage
D. Luster
Answer: C
Rationale: Cleavage occurs when a mineral breaks along specific planes where the atomic
bonds are weaker.
8. A mineral that breaks into irregular, jagged, or curved surfaces is said to have:
A. Perfect cleavage
B. Fracture
C. Streak
D. Tenacity
Answer: B
Rationale: Fracture is the term used for non-planar breakage of a mineral.
9. Specific Gravity is a measure of a mineral’s density relative to the density of:
A. Iron
B. Quartz
C. Air
D. Water
Answer: D
Rationale: Specific gravity is the ratio of the weight of a mineral to the weight of an equal
volume of water.
100% PASS-GSU
1. Which of the following is NOT part of the definition of a mineral?
A. Organic composition
B. Inorganic solid
C. Naturally occurring
D. Ordered internal crystalline structure
Answer: A
Rationale: Minerals must be inorganic; organic substances like coal are not considered
minerals in a geological sense.
2. Which mineral is the softest on the Mohs Hardness Scale?
A. Fluorite
B. Gypsum
C. Calcite
D. Talc
Answer: D
Rationale: Talc is the softest mineral with a Mohs hardness of 1.
3. What is the hardest known mineral on the Mohs Scale?
A. Quartz
B. Diamond
C. Corundum
D. Topaz
Answer: B
Rationale: Diamond is the hardest mineral, rated at 10 on the Mohs scale.
,4. What property refers to the color of a mineral in powdered form?
A. Luster
B. Hardness
C. Cleavage
D. Streak
Answer: D
Rationale: Streak is the color of a mineral’s powder, often more reliable for identification
than the mineral’s external color.
5. Which mineral reacts (effervesces) when a drop of dilute hydrochloric acid is
applied?
A. Calcite
B. Halite
C. Quartz
D. Hematite
Answer: A
Rationale: Calcite is a carbonate mineral that reacts with acid to release carbon dioxide
gas.
6. Which mineral is strongly attracted to a magnet?
A. Magnetite
B. Pyrite
C. Galena
D. Hematite
Answer: A
Rationale: Magnetite is a natural magnet and is strongly attracted to magnetic fields.
, 7. The tendency of a mineral to break along smooth, flat planes of weakness is
called:
A. Hardness
B. Fracture
C. Cleavage
D. Luster
Answer: C
Rationale: Cleavage occurs when a mineral breaks along specific planes where the atomic
bonds are weaker.
8. A mineral that breaks into irregular, jagged, or curved surfaces is said to have:
A. Perfect cleavage
B. Fracture
C. Streak
D. Tenacity
Answer: B
Rationale: Fracture is the term used for non-planar breakage of a mineral.
9. Specific Gravity is a measure of a mineral’s density relative to the density of:
A. Iron
B. Quartz
C. Air
D. Water
Answer: D
Rationale: Specific gravity is the ratio of the weight of a mineral to the weight of an equal
volume of water.
