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Make - the proportions to which a diamond has been cut. A good make will have proportions that maximize the brilliance and fire of a diamond. A poor make will lead to a diamond that has little sparkle due to the inability of the cut to properly reflect light. Measurement - the dimensions of a gemstone, expressed in millimeters (i.e., height, width, and depth). Melee - diamonds that weigh less than 1/5 of a carat (0.20 ct. or 20 points). Natural - part of the original crystal surface remaining on a finished gemstone. Needle - a long, thin, included crystal. Pavilion - the bottom portion of a diamond, just below the girdle. Pinpoint - a very small inclusion, seen under 10X magnification as a very tiny dot. Pinpoints can be single or in groups. Point - a weight measure equal to one one-hundredth of a carat. (A 0.50-carat diamond is equivalent to 50 points). Polish - a grade given to the external finish of a stone. The polish scale ranges from poor to excellent. Proportions - general category describing the various cut parameters of a gemstone. Report - refers to a diamond grading document detailing unique characteristics of a diamond. Shape - the outline of a diamond expressed as round, oval, marquise, emerald cut, etc. Sight Holder - diamond dealer or manufacturer invited by the Central Selling Organization (CSO) to buy rough or uncut diamonds at a "sight" or inspection. Symmetry - a grade given to the overall uniformity of a stone's cut. The scale for symmetry ranges from poor to excellent. Surface Graining - surface indication of the crystal's structural irregularity. Table - the large, flat, octagonal facet on the top of a diamond. Table Percentage - the width of the table divided by the total diameter of the diamond. Ultraviolet Light - used as a means of detecting fluorescence in gemstones.
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