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Name: Jerolyn W.
Status: Educator
Age: 40s
Location: N/A
Country: N/A
Date: April 29, 2004

Is there anything that can scratch a diamond? Will another diamond scratch it?

A diamond has a hardness of 10 on a scale of 10 known as Mohs Hardness Scale. A diamond can scratch any other mineral and only a diamond can scratch a diamond.

An old myth/legend to test for a diamond was to see if the mineral would scratch glass and if it did, it was a diamond. Actually there are many other minerals that will scratch glass including quartz (very common), corundum (gem forms are called sapphire and ruby), garnet, topaz, and others.

Steven Miller

Generally, another diamond will scratch it. I do not recommend scratching jewel grade or cut diamonds on anything (like a mirror) or with another diamond. There may be planes of weakness in the natural crystal structure and the diamond can split.

Pat Rowe

Diamonds will scratch diamonds, with difficulty. However, just recently synthetic "diamonds" have been made that are harder than "natural" diamonds. This is very recent so a Google search should snag a reference easily.

Vince Calder

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