Who’s Hardest Now?

Moh’s scale of mineral hardness is based on the basic concept that a harder mineral will scratch a softer mineral. This can be used as a basic test to assist in making a rough identification of minerals found in the field. The Mohs scale starts at one with the softest mineral, talc, and ends at 10 with the hardest mineral, diamond. Or does it? There’s a new man-made mineral that will scratch diamonds! According to a paper in a recent issue of the National Science Review written by a team including Shuangshuang Zhang (Yanshan University, China), buckminsterfullerene (C60) has been subjected to high pressures and temperatures to 1,200°C. The result? “A disordered carbon material that is so hard that it scratches diamond.” Is it time to add 11 to the Mohs scale?