Mohs scale
Rockwell hardness
The pH scale does not measure hardness it measures the acidity or otherwise of substances
The Mohs scale is used to determine the relative hardness of minerals.
The scale used to measure the hardness of a mineral is called the Mohs scale. It ranges from 1 (softest) to 10 (hardest), with each number representing a different level of hardness.
The Mohs scale. # Talc # Gypsum # Calcite # Fluorite # Apatite # Feldspar # Quartz # Topaz # Corundum # Diamond The Mohs scale, however, is an purely ordinal scale. For example, corundum (9) is twice as hard as topaz (8), but diamond (10) is almost four times as hard as corundum. Check the related link for more info.
hardness
The element neon has no hardness on either moh's hardness scale or rockwell scale unless it is frozen. These scales measure only solids.
The Mohs scale is used to determine the relative hardness of minerals.
Opal has a hardness of around 5.5 to 6.5 on the Mohs hardness scale, which means it is relatively soft compared to other gemstones. This makes opal prone to scratching and requires gentle handling and care.
The scale used to measure the hardness of a rock is called the Mohs scale. It ranges from 1 (softest) to 10 (hardest) with each level representing a different mineral's ability to scratch another.
it measure the hardness of material.
Hardness of a mineral - the answer in in the title "Moh's hardness scale".