Example 1: From one piece of rough a diamond has been cut to Ideal proportions, retaining a weight of one carat. The light is totally reflected through the top.

Example 2: The second piece of rough has been "spread" in its cutting, resulting in a diamond weighing approximately 1.40 ct. Note: The girdle is thicker, the table is much larger, the angles are exaggerated, all at the expense of that diamond's ability to reflect light.

Therefore, one can see that the value of a diamond can vary as much as 40% in the cutting alone.

You're probably familiar with the term carat, the unit of measurement used to indicate the weight of gemstones. (This should not be confused with karat, the term jewelers use when stating the relative fineness of gold.)

You want to be sure your jeweler is clear about the terms that are used in reference to the weight of a diamond. One carat is equal to 1/5 of a gram. For diamonds less than one carat, weights can be expressed in terms of halves and quarters (as long as they are at least half or a quarter). For more precision, the carat can be divided into 100 points. Thus, a 10 point diamond is 1/10 of a carat.

The most important thing to know about weight is that weight isn't everything. You may be searching with a half carat or one carat stone in mind. That's fine. But you may be faced with a choice between a one carat stone of lesser value than a 90 point stone with higher grades for cut, color, and clarity. Sometimes less is more, even in the world of diamonds. Be flexible-you may get a more pleasing stone.

Of course, a well-cut, high grade, one carat diamond will certainly be more valuable than a similarly cut high grade 90 point stone. And, because of its rarity, a two carat well-cut highly graded diamond will be worth much more than twice what a one carat stone would cost.

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