Scientists Created a Crystal That's 58% Harder Than Diamond

Hard stuff Mr. Barlow's Blog

Superhard Materials: Beyond Diamond Hardness

Carmeltazite: Extraterrestrial Mineral Harder And Rarer Than Diamonds

Wurtzite Boron Nitride

Scientists Just Created a New Glass That's Tougher Than Diamond

Imperfections in natural diamond: the key to understanding diamond genesis and the mantle

Can scientists make a material harder than a diamond? - Quora

Beyond Diamonds: Exploring the Frontiers of Hardness in Nature and Technology

Scientists discover ultra-strong diamond created by a dwarf planet