Use the table to answer the question.

Mineral

Hardness

Cleavage/Fracture

Luster

Obsidian

5

Fracture

Vitreous

Halite

2.5

Cubic cleavage

Vitreous

Fluorite

4

Octohedral

Vitreous



An unknown mineral specimen is not scratched by a penny and does not exhibit cleavage. The mineral is most likely to be:

(1 point)
Responses

obsidian

halite

fluorite

The mineral is most likely to be obsidian.

Based on the given table, we can determine the mineral that is not scratched by a penny and does not exhibit cleavage.

The mineral with these properties is obsidian. Therefore, the unknown mineral specimen is most likely obsidian.

To answer the question, we need to analyze the information in the table. In this case, we are looking for a mineral specimen that is not scratched by a penny and does not exhibit cleavage.

From the table, we can see that obsidian has a hardness of 5, fracture as its cleavage/fracture characteristic, and vitreous as its luster. Halite has a hardness of 2.5, cubic cleavage, and vitreous luster. Fluorite has a hardness of 4, octahedral cleavage, and vitreous luster.

Knowing that a penny has a hardness of approximately 3.5, we can conclude that the unknown mineral specimen is harder than a penny. Since the unknown mineral also does not exhibit cleavage, we can eliminate fluorite from the options because it has octahedral cleavage.

Therefore, the most likely answer is obsidian, as it is harder than a penny and has fracture as its cleavage/fracture characteristic.