Hardest mineral
Who
Diamond
What
10 total number
Where
Not Applicable ()

Diamond is a high-symmetry allotrope of carbon (C). It has a Mohs “scratch” hardness of 10, which makes it the hardest mineral known to date. Because the Mohs scale is not absolute, diamond is actually about five times harder than no. 9 (corundum) and some 700 times harder than talc (no. 1)! A quest for superhard materials brought scientists close to the development of synthetics that are believed to supersede diamond in their resistance to scratching, like high-pressure boron nitride.

Natural diamonds are mined mostly from the igneous rock called kimberlite, which originates in the Earth’s mantle and acts as an “elevator” for diamond crystals formed deep below the surface. Today, the bulk of diamond production by value comes from mines in Botswana, Russia and Canada. However, most of the crystals used in industrial applications (like abrasives and cutting tools) are actually produced in factories at high pressure and temperature simulating those in the Earth’s mantle.