The hardness is 3-4 on Mohs scale.
Dolomite has a hardness of 3.5-4 on the Mohs scale of hardness.
Diatomite has a hardness of around 5.5 on the Mohs scale of hardness.
It's called the Ore
The hardness of Limonite is 4 t0 5.5 on the mohs hardness scale.
Azurite has a hardness of 3.5 to 4 on the Mohs hardness scale.
flint is a type of quartz, so it has a hardness of about 7 on the mohs scale of hardness
Nickel has a hardness of 4 on the Mohs scale.
The Mohs scale is used to determine the relative hardness of minerals.
This scale was proposed by the Austrian geologist Friderich Mohs.
Aluminum Oxide is roughly 8.5 - 9.0 on the hardness scale.
Granite is not assigned a number on the Mohs scale of hardness. The Mohs scale is a measurement of the relative hardness of minerals. Because granite is a rock composed of a variety of minerals, only the individual minerals which compose it have a Mohs hardness.
It is about 2.5 in the Mohs Hardness Scale.