Question

According to Moh’s Hardness Scale, which of the following minerals is harder than Quartz but softer than Corundum?

• A. Orthoclase
• B. TOPPUS
• C. Fluorite
• D. Diamond

Answer 1

Answer:

B. TOPPUS

Moh's Hardness Scale

Understanding the Scale

• The Mohs scale of mineral hardness is a qualitative ordinal scale, ranking minerals from 1 (softest) to 10 (hardest) based on their ability to scratch one another.

• Developed by German mineralogist Friedrich Mohs in 1812, it is widely used in geology and mineralogy for mineral identification.

Mineral Hardness Values and Positions

• Quartz is assigned a hardness of 7 on the Mohs scale.

• Corundum (which includes ruby and sapphire) has a hardness of 9.

• Minerals harder than Quartz but softer than Corundum fall within the hardness range of 8.

Topaz: A Mineral with Intermediate Hardness

• Topaz is a silicate mineral that ranks 8 on the Mohs Hardness Scale.

• This places Topaz directly between Quartz (7) and Corundum (9) in terms of scratch resistance.

• Therefore, Topaz can scratch Quartz but can be scratched by Corundum.

• Common occurrences of Topaz include Brazil, Sri Lanka, and the United States. It is often found in granitic rocks and pegmatites.

• Topaz is valued as a gemstone and is known for its transparency and various colors, including yellow, blue, pink, and colorless.