Diamonds are sometimes called a girls best friend, but how are they made? It all started deep in the earth, around 150-200 kilometers. At this depth carbon-containing materials are subjected to high temperatures and pressures. The diamonds are then thrown out from the eruption of a volcano. Synthetic diamonds are made in molten metals within the volcano, metals that diamonds can be made in are iron or nickel. The diamonds are crystallized in these metals. Unlike the other form of the elemental carbon, graphite, diamond can be stable under higher temperatures and pressure. If a diamond is pure then it is colorless and if there is any color, it is due to the fact that the imperfections were trapped inside when the diamond was made. This should not be confused with any color that the diamond gives off when it is put up to light. Diamonds conduct heat and thus they feel cool to the touch. Some diamond experts can tell a real diamond from a fake by putting it on his/her tongue. If it is real it should be cold, kind of like a metal in your mouth.
Diamonds are great. I never new that they were made in a volcano. Although diamonds may be a girls best friend, I've always heard that they were not actually a rare diamond. That they were actually common, but most of the worlds supply is controlled by one person and that is why they are so expensive. Needless to say, I will probably still buy one at some point in my life. Not I know what to look for when I am buying a diamond. I will make sure to stay away from the fakes.
Baird, Colin. Chemistry in Your Life. 2nd Ed, W.H. Freeman and Company, New York. 2006. (195-196)