Gemologists confirm that the cut of a diamond is the most important criteria to its brilliance. A diamond having been cut in the proper proportion will scatter more light than one improperly cut. In effect, if a diamond has a good color and clarity but was not cut properly, it will lose its appearance. By the cut, we refer to the finishing, dimensions, and the reflection of light as well as the polishing and symmetry. These qualifications are essential to the beauty and quality of a diamond which only an experienced craftsman can master.
Diamonds are also graded by their color. The most sought after color is a transparent white (or the absence of color) which is what determines its value. The GIA (Gemological Institute of America) has standardized a simple but detailed system for grading diamonds from colorless to colored (from white to yellow and even to brown). Different letters of the alphabet identify the grading. The scale begins with the letter D (which represents the transparency) right on to the letter Z which reflects the increase in color. All to say a perfect diamond is not an A but a D.
Since diamond gems come from deep within the earth, most of them will have inclusions and surface defects called blemishes. In most cases, inclusions may be crystals of a foreign material or structural imperfections such as tiny fractures. Diamonds with the least inclusions are rarer and the most valuable. By applying the international system of classifying diamonds (mc) created by the GIA, the clarity grade is determined by its overall appearance. Clarity is one of the 4C’s in diamond rating, the others being carat, color and cut. Under ten times magnification, a clarity grade is determined by the positioning, the quantity, the size, the color and the nature of impurities.
Carat weight specifically refers to a diamond’s weight and is one of the elements which determines its value. A one carat diamond is comprised of 100 points. Hence, 25 points equals a quarter of a carat while a 50 point equals half a carat. Larger size diamonds being rare, the value of the diamond increases considerably.