Our HistoryGlossary
Bezel Facets - On round brilliant diamonds, these are the eight large kite-shaped facets on the crown. Also called top main facet.
Brilliance - Describes the reflections of white light coming from a diamond.
Brilliant Cut Diamond - Round diamond with 58 facets. Round brilliant cut diamonds are extremely brilliant.
Carat - The standard unit of measurement of the weight of a diamond. One carat equals 1/5 of a gram or 1/142 of an ounce. 1 carat=100 points.
Cavity - An inclusion consisting of a large or deep opening in the diamond.
Clarity - The degree to which a diamond is free from blemishes. Clarity is graded on a scale from Flawless to Imperfect.
Clarity Enhancement - Any process used to improve the clarity of a diamond. This may include filling fractures and cavities with glass or resin.
Cleavage - A break in a diamond that is parallel to one of its crystallographic planes. Cleavage may be caused by inherent internal strain or by a sharp blow. The break may extend to the surface of the diamond.
Crown - The part of the diamond above the girdle. It consists of the table and the crown facets below it.
Crown Angle - The angle measured between the girdle plane and the bezel facets. Along with the table size, the crown angle helps determine the amount of dispersion displayed by the diamond.
Crown Height - The part of the diamond that is above the girdle.
Crown Height Percentage - The crown height expressed as a percentage of the average girdle diameter.
Crystal - A type of inclusion. A crystal can be a mineral deposit trapped inside the diamond.
Culet - A small face forming the bottom of a faceted gem.
Cut - The cut (make) of a diamond refers to the proportions given to the polished diamond by the diamond cutter. The cut is the most important of the 4'Cs (cut, color, clarity, carat) in determining the diamond’s overall beauty.
Depth - The distance between the table and the culet as measured in millimeters.
Dispersion - The fiery rainbow colors emanating from a diamond as white light is broken up into colors.
Eye-Clean - Describes a diamond that has no inclusions visible through the table to the unaided eye.
Facets - The polished planes on the surface of a diamond.
Feather - A fracture in a diamond that looks like a white feather.
Fire - The rainbow colors seen in a diamond as a result of dispersion.
Fracture - A chip or break on a diamond that is not in the direction of a cleavage plane. Irregular in shape, fractures usually appear step-like or splinter-like.
Fracture Filling - A diamond enhancement process whereby a cavity in a diamond is filled with an artificial substance.
Girdle - The outer edge of a diamond that forms a band around the stone. The girdle can be faceted, polished, or unpolished
Girdle Thickness - The measurement of the percentage of the diamond’s average girdle diameter.
Grading Report - Issued by an independent laboratory, it is sometimes called a “certificate,” although labs do not actually “certify” diamonds. The grading report should accurately describe the proportions, weight, color, clarity, symmetry, polish, and possible fluorescence seen in the diamond. Some labs, such as GIA and AGS, are felt by many experts to be more consistent and stringent in their grading than other labs.
Inclusion - A naturally occurring imperfection in a diamond. Some examples are feathers, crystals, needles, clouds, and pinpoints.
Laser Drilling - A diamond enhancement technique whereby a laser is used to drill to an inclusion, which is then bleached to enhance the diamond’s appearance.
Lower-Girdle Facet - The facets on the pavilion of a round brilliant just below the girdle.
Pavilion - The portion of the diamond below the girdle.
Pavilion Angle - The angle measured between the girdle and the pavilion main facet.
Pavilion Main Facets - The eight facets found on the pavilion of a round brilliant diamond. Their points touch the girdle.
Pinpoints - Very small inclusions in a diamond.
Point - 1/100 of a carat. For example, a 1/4 carat diamond weighs 25 points.
Polish - The way the cutter finishes the facets on a diamond. Labs grade finish from poor to excellent.
Scintillation - Sparkle. The tiny flashes of light noticeable in a diamond when the observer moves his/her head.
Shape - There are eight common diamond shapes: round, marquise, pear, oval, heart, princess/radiant, emerald, and trillion. There are also other shapes created and sold by manufacturers.
Star Facet - One of the eight triangular facets found on the upper crown section (next to the table) of a brilliant-cut diamond.
Symmetry - Labs grade symmetry from poor to excellent, based on the diamond’s proportions and the relation of one facet to another (meet-point faceting).
Table - The largest facet that sits on top of a diamond. This is where most of the light enters and exits a diamond.
