Fancy-shape diamonds and round diamonds are popular choices for people who buy jewelry. - Photo by Robert Weldon/GIA
The simple balance scale weighs gems, but many jewelers today use electronic digital scales. - Photo by Eric Welch/GIA
A house fire turned the diamond on the left white and cloudy. The stone was recut to take away the burned area. This made the diamond smaller, but as you can see from the diamond on the right, the damage is gone. - Photo by Nicholas DelRe/GIA
The most common shape for rough diamond is the octahedron, which looks like two pyramids stuck together, bottom to bottom. Notice the pyramid points on these rough diamonds. - Photo courtesy De Beers
Octahedron Up Close
Here is a close view of a diamond crystal whose shape is the octahedron. Crystals that are almost perfect in shape and clarity are called “glassies.”
Looking like they are frozen in space, these dark inclusions look very interesting. However, because they are very noticeable, the clarity is affected and this makes the diamond less valuable. - Photo by John I. Koivula/GIA
No two diamonds have exactly the same clarity characteristics in exactly the same locations. This fact helps gemologists identify individual diamonds. - Photo by John I. Koivula/GIA
How Diamonds Form
Where do diamonds form? At a certain depth beneath the earth’s surface. Heat and pressure form diamonds, which are then pushed to the surface.
Diamond and Graphite
Diamond and graphite are both made of carbon, but their atoms are arranged in different patterns. That's why diamond is hard and graphite is soft. Did you know that pencils are made of graphite? Watch the video to see how atoms make up diamond and graphite!
Learn what makes a diamond brilliant, and what “fire” and “scintillation” mean.