Intro to Mohs Hardness Scale

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Question 1: Is the range of the Mohs Hardness Scale 0 to 5?

• No

• Yes

Answer explanation

No. The scale is from 1 to 10. 

Are any metal tools in the list of materials on the Mohs scale?

• No

• Yes

Answer explanation

No. All the materials are naturally occurring pure minerals (crystals) in the form of rocks.

Does the hardest material in the Mohs Hardness Scale have a score of 10?

• No

• Yes

Answer explanation

Yes. And 1 is the softest.

Does diamond have a Mohs Hardness value of 1?

• No

• Yes

Answer explanation

No. Diamond has a hardness of 10.

If an unknown stone can be scratched by apatite (Mohs Hardness of 5), does that unknown stone have a Mohs hardness greater than 5?

• No

• Yes

Answer explanation

No. Its value would be less than 5.

Can the Mohs Hardness Scale be used on non-rocks such as metals?

• No

• Yes

Answer explanation

Yes. It can be used on any solid.

Can a material have a Mohs Hardness Scale value between 0 and 1?

• No

• Yes

Answer explanation

Yes. The example we showed is a wax candle.

Is the 6^th object on the Mohs Hardness Scale 2-times as hard as the 3^rd object on the scale?

• No

• Yes

Answer explanation

No. The scale is a rank from 1^st to 10^th hardest, but each interval is different so we cannot do math to compare them (it turns out the 6^th one is 7-times as hard as the 3^rd one).