But the fossil record, and the dating of diamonds, indicate that this carbon is at least three billion years older than animal and plant life. The carbon was incorporated into our solar system, where it is the fourth most abundant element. This carbon, plus some that was brought to Earth on meteorites, may well be the source of diamonds, Haggerty says. The study of diamond has seen a recent burst of activity as new research methods have become available. The new theory is based on an evaluation of this scientific literature, he notes.
Chondrites contain several forms of carbon, including diamonds older than our sun.
Scientists have shown that most diamonds are brought from the Earths interior to its surface by volcanoes. But the volcanoes that bring forth these precious stones are much younger than the diamonds themselves, according to Haggerty. This combination of old diamonds and young volcanoes indicates that the diamonds were already formed when magma brought them to the surface. Additionally, there were two geologically short time periods during which hundreds of diamond-producing volcanoes erupted all over the Earth. One group erupted about one billion years ago, and the other 100 million years ago.