Two diamonds of equal carat weight might vary greatly in value depending upon their cut, color and clarity. This is important because when mounted, one diamond may appear larger than the other, although they actually weigh the same. If size is important to you, focus on diamond measurements as opposed to carat weight. Diamonds that look big for their weight may have reduced brilliance and fire so always insist on great cut.

An increase in carat weight does not produce the same increase in millimeter diameter. For example, there is a 25% increase in carat weight from 1.00 carats to 1.25 carats but less than 8% increase in diameter (6.5 to 7.0 mm). This concept, along with the increased price per carat, explains why prices increase dramatically in order to get noticeably bigger millimeter size.

Over 1 million rough diamonds must be mined before one is found that can be cut into a 1.00 carat finished diamond. Because large diamonds are so rare, they generally have a greater value per carat. If all other factors are equal, the heavier the diamond, the greater its cost will be. For example, the price of a two-carat stone will be several times higher than four 50-pointers of equal quality.

 A diamond's cut is graded by several measurements. Its depth percentage (a measurement of the height vs. the width of the stone) and its table percentage (a measurement of the diameter of the top facet of the stone vs. the stone's average width) are two key factors in determining the quality of a diamond's cut. These percentages are detailed on the GIA or AGSL Diamond Grading Report that accompanies every Adiamor loose diamond. Experts express differing opinions on the best table size (the diameter of the largest facet on the top of the stone) and the best depth for a diamond, because these two factors alone are not sufficient enough to accurately judge a diamond's cut. Other factors such as crown angle, girdle thickness, culet size, polish and symmetry all play a role in judging a diamond's overall cut quality.

When it comes to buying a diamond for that special lady in your life, whether it is an engagement ring, a pendant, a bracelet, or some classic studs, size isn't everything... but it’s a lot. If you choose a diamond that’s too small, she might have to pull out a magnifying glass every time she wants to admire it (and it’s not very impressive to all of her friends, either). If, on the other hand, you buy a rock that’s way too big, she may not wear it for fear of theft (plus, most women are wary of looking ostentatious). Choosing the right diamond requires a lot of thought, but if you follow a few simple guidelines, you should be able to pick the right stone for every occasion.