Not even that, quite. There are two known naturally occurring minerals that are harder than diamond: wurtzite boron nitride, and lonsdaleite (another carbon al

Not even that, quite. There are two known naturally occurring minerals that are harder than diamond: wurtzite boron nitride, and lonsdaleite (another carbon allotrope). They just don't occur in very large quantities. Ref: http://www.newscientist.com/article/dn16610-diamond-no-longer-natures-hardest-material.html http://www.newscientist.com/article/dn16610-diamond-no-longe...