In most simple words, the actual weight of the diamond is termed as the carat weight. Moreover, about 0.2 grams is equivalents as of a Carat and obviously has got no relation with the term of karat, which is the basic unit in which the purity of gold is measured. However, the carat weight must not wholly be relied upon as the primary indicator of the size of the diamond. Such dependence of carat weight is considered a norm among the diamond buyers.
Most importantly, the factor to be referred upon more profoundly is the size of the diamond. Though the factors of weight and size are correlated, they are absolutely two different things. In general, the size of a diamond is calculated by three units of measurements, namely the depth, the length and the width. The major dimensions across the diamond top are referred by its width and length.
When considering the different diamond cuts, the valuing of its physical dimension also alters based on its length, width, and depth. Take the example of the round brilliant cut firstly. Since there is only a single diameter for the shape, the calculated measurements of length and width will almost be the same. Meanwhile, depending on the elongation of the shape, these quantities will differ from each other in the case of fancy diamonds.
The basic distance from the bottom point or culet to the top of the diamond is referred to as the depth of the diamond. This is considered as the third measurement of diamonds. The apparent size of the diamond cannot be correctly indicated by its depth. However, depth is significant for evaluating the cut of the diamond. All the while, in the ring setting, the depth is usually hidden.
When a buyer is planning to purchase numerous similar-looking diamonds, they may get confused with its weight and size. Take, for example, two round brilliant cut diamonds of same G color, same price per carat, same excellent cut and VS2 clarity. Suppose one of the diamonds will be 1.05 ct and the other 1.00 ct, then the former one is going to be the more costly, around 5% than the normal.