Unlike other commodities, such as most precious metals, there is a substantial mark-up in the retail sale of gem diamonds.

The technique, while very expensive, produced gem diamonds of high quality and large size.

Wives don't seem to accept the idea that a synthetic gem diamond is the same in substance and quality as a natural diamond.

The price for synthetic and natural gem diamonds is about the same - around $2,000 a carat.

Nitrogen is by far the most common impurity found in gem diamonds.

Gold, chromium, gem diamonds, platinum, copper, salt and natural gas.

The specific gravity (SG) or density of a gem diamond is fairly constant at 3.52.

As part of the settlement, persons who purchased gem diamonds from 1 January 1994, to 31 March 2006, may be eligible for compensation.

Other characteristics also influence the value and appearance of a gem diamond.

Since the early 1980s, the country has been the world's largest producer of gem diamonds.