Gemstone/Diamond Carats

Is there a woman today who has not been wandering the television channels and become entranced by a shopping channel? Especially if there are bright shining jewels on the screen? If so, she is made of stronger stuff than I am. One thing those programs have done, however, is educate those who are listening while hypnotized by the screen. We all want a perfectly cut diamond that is just as bright on our finger as it is in those television lights...and we'd like it to be as many carats as possible.

When is a carat not a carat?

In 1913, in the United States, .200 grams or 200 milligrams was established as 1 carat. That is the accepted standard around the world. A carat is an expression of the weight of the stone. Size is also expressed as points. It's easy to hear the number of points and think number of facets, but points has nothing to do with facets. If a stone is .50 carats or 50 points, it's 1/2 carat. 2.00 carats or 200 points is 400 milligrams.

Because a carat is a measurement of weight it's possible for a smaller diamond to weigh more than a larger diamond...if we measure by diameter. The difference is in the cut. If a stone with a small diameter is cut DEEP, it can weigh more than than a stone with a larger diameter that has a shallow cut.

Why is a carat not a carat?

Diamond cutters can get more dollar value out of a rough stone by if they produce undersized stones. Research tells me that a very fine cut stone would measure 6.4 to 6.5 millimeters. That same source tells me that most "1 carat" diamonds today measure between 5.9 ad 6.3 millimeters. If a well cut diamond had the same diameter they would actually weigh .75 to .99 carats. The under sized stones are not a true 1 carat in weight and acceptable brilliance. The cut of a stone maximizes how light travels through it. If the cut is done with the object of removing as little weight as possible, brilliance is sacrificed.

The GIA, EGL, IGI may be included with a stone, but those reports do not address or assign a grade to the cut. The buyer must examine the symmetry, polish, depth, girdle thickness and more.