Dogtooth calcite
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Friedrich Mohs

Friedrich Mohs was a scientist who lived about 200 years ago in Europe.

Friedrich's liked to identify minerals. He looked at a crystal closely and checked its hardness to decide which kind it was. He knew that some minerals could scratch other minerals. If one mineral can scratch another, it must be harder than the mineral it scratched. He found that diamonds are the hardest mineral because they can scratch any other.

Friedrich made a scale from one to ten to describe the hardness of different minerals. He gave harder minerals larger numbers and softer minerals smaller numbers.

We still use Friedrich's scale today! It's called Mohs Hardness Scale.

Last modified May 6, 2003 by Lisa Gardiner.

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