Composition

• Diamonds are solid lumps of pure crystallized carbon. They are formed deep within the earth by intense pressure and high temperatures. Carbon atoms under these conditions bond and begin to crystallize. The crystal grows at varying speeds depending on the conditions surrounding it. This results in the many different-size diamonds unearthed in the world today. Diamonds are brought to the surface by volcanic eruptions. If they were not transported to the surface quickly, they would lose their molecular structure and become balls of graphite along the way.
  
  

Durability

• The Mohs scale of hardness was developed in 1812 by Frederick Mohs and has been used ever since to measure the durability of gemstones. The scale ranges from one to ten, with ten being the hardest and one being the softest. Currently the hardest substance listed on the Mohs scale is diamond, which is rated as a ten. The carbon atoms that make up a diamond bond into a cubic pattern. As the diamond solidifies, more carbon atoms are added. The structure eventually begins to crystallize, but it is the intense four-sided bond of the carbon atoms that gives a diamond its hardness.
  
  

Refractive Index

• The refractive index of a diamond is a way of measuring how it absorbs and reflects light. This is what gives a diamond its sparkle. When light travels through a substance, it slows down. Clear substances are "refractive" and bend light as it travels through. Refractive substances, however, do not typically give much resistance to the passing light. Diamonds are an exception. A diamond is dense and slows light to a greater degree than any other refractive substance on Earth except moissanite. This is why diamonds sparkle. They literally do "catch" the light.
  
  

Shaping

• Diamonds may be the hardest substance on Earth, but they are not impenetrable. These gems have weak areas known as "cleavage points." If a diamond is struck along a cleavage point, it will break. Jewelers use specially cut diamonds to break rough diamonds along their cleavage points to begin the shaping process. A special saw called a scaif is used to shape the rough material into gems. As the scaif cuts, its blade continually picks up diamond dust. It is this very fine, yet very sharp dust that makes the blade sharp enough to shape the diamond.
  
  

Uses

• The versatility of diamonds and particularly their dust is unmatched by any other gemstone. Diamond dust is useful for lacing saw blades and drill bits. The dust is also used to facilitate electron emissions in some flat-screen television sets. The beauty industry, however, values diamond dust extremely highly and includes it in products like facial powder, nail polish and premium nail files. The dust can even be used for jewelry in lieu of an actual diamond. Jewelers seal diamond dust into jewelry settings to give other gems added sparkle.