How to Perform the Test

1. Select a fresh surface

2. Hold the sample and attempt to scratch it with the point of an object of known hardness

In this example, we use a sharp quartz crystal (H=6)

3. Press the object firmly but lightly against the unknown sample

4. If the test object is harder, you should see and feel a definite "bite" into the sample

5. Inspect for an etched line

In this case, we notice a deep scratch in the sample, which indicates it's hardness is less than 6

6. Repeat several times, always with a sharp point and a fresh surface

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