[stephengillie]

We have tons of carbon on earth. We inhale and exhale it all the time. It's one of the top 4 atoms in the universe, along with hydrogen, oxygen, and nitrogen.

Turning matter from diamond to carbon-fiber, or anything else, takes much energy. This is why diamond is so hard to cut - the carbon atoms have very strong magnetic bonds, and separating them takes a lot more force than separating iron atoms when cutting steel.