Can Diamonds Be Scratched?

Diamonds are the hardest known substance in the world. They have a value of 10 on the Mohs Hardness Scale, which is the highest possible value. Diamonds cannot be scratched by anything except another diamond.

Significance

The hardness of diamonds increases their worth as gemstones and also makes diamonds valuable in industrial applications, such as drills, scratch-proof films and surgical tools. Between 75 and 80 percent of diamonds are used in industrial applications.

Fun Fact

The Mohs Hardness Scale is relative, not linear. Diamond is much harder than corundum, which has a hardness of 9. Diamond would have a value of 42 on a linear hardness scale.

Considerations

If a diamond is scratched by anything other than another diamond, it is an imitation diamond. Imitation diamonds are usually created from glass, cubic zirconia or moissanite. Cubic zirconia has a hardness of 8.5, while moissanite has a hardness of 9.25.

References

• California State Polytechnic University, Pomona: Hardness
• Cornell University: Is It Real or Is It Moissanite?
• Emporia State University: Everything You Always Wanted to Know About Diamond

Resources

• University of Wisconsin: Buckyballs, Diamond, and Graphite