http://b4hntuy3fimfh2227vf4f74emnya7p35i5brtqujs6leqvtclfwvjbqd.onion/doc/physics/diamonds-crookes/The%20Project%20Gutenberg%20eBook%20of%20Diamonds,%20by%20William%20Crookes..html
I have done my best to explain the fiery
origin of the Diamond, and to describe the
glowing, molten, subterranean furnaces
where they first begin mysteriously to take
shape. I have shown that a diamond is the
outcome of a series of Titanic earth convulsions,
and that these precious gems
undergo cycles of fiery, strange, and potent
vicissitudes before they can blaze on a ring
or a tiara.