What is the hardest rock?

2 answers

ANSWER #1 of 2

My chemical romance ;-;

ANSWER #2 of 2

Diamond was once thought to be the hardest and the most incompressible material on earth, either natural or man-made. Although diamond is still considered the hardest, the bulk modulus of the metal osmium has recently been found to be 476 GPa.

What is the hardest rock?

Add your answer to this list