Comparing the value of stones by weight is like comparing the value of paintings by size. A wall-sized canvas by an unskilled artist may be bigger than a miniature by Rembrandt, but it will not be worth more. The standard used to measure diamond weight is the carat. A carat equals 1/5 of a gram (or 1/142 of an ounce). Each carat is further divided into points, each point representing 1/100th of a carat. While weight may be the least important of the four Cs in determining value, it may be the easiest of the four Cs to gauge accurately and is the most objective. All that is required is a delicately balanced scale capable of weighting extremely small weights. Yet, despite the ease of measurement and the relative unimportance of diamond weight, there are some facts you should understand about weight and price.
First, as diamonds increase in size, their cost tends to increase geometrically rather than arithmetically. Thus, a one-carat diamond may cost more than twice as much as a one-half carat stone of equal quality. Also, as previously stated, weight does not always enhance the value of a diamond. In fact, when a stone is improperly cut, added weight may serve only to reduce its brilliance. For these reasons, you should consult with an American Gem Society titleholder or individual regarding the question of carat weight, especially as it relates to the quality of the diamond's cut.
