Diamonds are the hardest known precious stones on Earth. They record a 10 on the standard Mohs scale of hardness, a scale that peaks at 10. Their extreme hardness originates from the combination of heat and pressure deep within the Earth over long periods of time. Ultimately, when a diamond is mined, it is mined in a rough form and in various shapes, colors and sizes.

Diamonds are mined primarily through pipe mining. Volcanic eruptions deep within the earth bring diamonds close to the surface where they can be mined. Pipe mines run far down, the deepest of which are up to 100 miles down. Large rocks containing diamonds are blasted out of the Earth, and brought up to be crushed and processed. The chunks are then sent to refineries to be screened for rough diamonds.

Mines located around the world in India, Russia, Canada, and Australia drill deep into the Earth and produce about 27,000 kg of diamonds a year. Of this, only about 20% of the rough diamonds mined are deemed good enough to be cut and polished for use in jewelry, while the rest are used for industrial purposes.

The rough diamonds that are good enough for jewelry are distributed by large companies, the largest of which is the De Beers Central Selling Organization. These rough diamonds are priced and sorted into over 5,000 categories, and traded to private buyers. These buyers ultimately send the rough diamonds to a cutting center to be cut and polished, after which they can be placed into a piece of jewelry.

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