In this articles we're going to cover what diamonds are made of and also the actual manufacturing of diamonds. Yes, we have reached the point where we can actually make a diamond. Isn't technology great? So what exactly are diamonds made from and how do they become diamonds? Well, believe it or not, diamonds are made of the same substance that the lead in your pencil and coal is made of. It's just that the atoms themselves are arranged in a way that make them tighter than any other substance. The bonds are formed when carbon exists at very high temperatures and under very high pressure. Natural diamonds are made very deep in the Earth about 180 km below the surface where high temperatures and pressure exist naturally. Under the earths crust is the mantel, which is made up of molten rock, metals and other materials. The temperature is very high at this depth - between 1100 degrees Celsius and 1400 degrees Celsius. The high pressures are produced by the weight of 180 km of rocks pressing down on it. This is how the diamond comes to be. Besides the carbon there are other substances like nitrogen and sulphur that can become trapped in the crystal. These substances can add color to the diamond, which under normal conditions is colorless. One of the rarest diamond colors is pink, which just happens to be the color of the diamond that Ben Afleck gave to Jennifer Lopez. It's worth is about $3 million. The question many people ask is, where exactly does the carbon come from to make these diamonds? Well, some of the carbon comes from the mantel of the Earth since the time it was formed, but some of it also comes from the bodies and shells of micro-organisms like algae in ancient oceans. This organic carbon was buried in rocks that were dragged down into the mantle because of plate tectonics and continental drift. The fact of the matter is, all life forms on Earth are carbon based, so technically if we were to fall into the ocean near a tectonic plate where rocks were being dragged underneath we could, in a million years or so, come back as a diamond. So, if that's how diamonds are made then how is it possible to make diamonds artificially? Well, producing a material that is harder than a natural diamond has actually been a goal of scientists for a very long time and in 2004, a group of scientists at the Carnegie Institution's Geophysical Laboratory in Washington, DC produced gem sized diamonds that are harder than any other crystals. These diamonds were made from a gas mixture at a rate that is 100 times faster than any other method that has been used to date. The crystals were so hard that they actually broke the equipment used and were made in less than a day. The crystals were grown using a special high growth-rate chemical vapor deposition (CVD) process that they developed. They then subjected the crystals to a high pressure, high temperature treatment to further harden the crystals. The way the process works is like this. Hydrogen and methane gas are bombarded with charged particles, or plasma, in a chamber. The plasma produces a chemical reaction that results in "carbon rain," that falls on a seed in the chamber. After this rain hits the seed the carbon atoms arrange themselves in the same structure as the seed. By using this method they have grown diamonds up to 10 millimeters across and 4.5 millimeters in thickness. If you ever saw the Superman episode where they needed to find a diamond to replace the one lost from the idol, you saw that it required placing carbon under a thousand tons of pressure for a million years. Superman of course squeezed the carbon in his hand and in seconds had a diamond. It seems we're not too far away from that now. |
