Diamond Education | Glossary

Blemish – a tiny mark or flaw on the outside surface of a diamond.

Bow-tie effect – a term used to describe a dark or open spot in the shape of a bow-tie that can be found in fancy shaped diamonds (Marquise, Oval, Pear).  A bow-tie usually runs horizontally (east to west) across the center of the diamond.

Brilliance – the amount of white light that reflects back from the diamond.

Carat – the weight of the stone.

Clarity – the amount of  natural characteristics or inclusions in the stone.

Color – the hue of the diamond.  Can be white, yellow, brown, or fancy (blue, pink, yellow).

Crown – the upper range of facets of a diamond above the girdle.

Culet – a single facet on the bottom of a diamond that runs parallel to the table.  It is designed to prevent the tip from chipping.

Cut – this refers to the proportions and angles of a diamond. A “well cut” diamond will internally reflect light from one mirror like facet to another and disperse and reflect it through the top of the stone (table). The more finely proportioned or cut diamond, the more brilliance or fire is dispersed.

Dispersion – the “break up” of white light into the spectrum of rainbow colors (also called Fire).

Facet – the cut polished angles and slants on the outer surface of the diamond.  The facets should be symmetrical.

Fire – flashes of colored light radiating from the diamond.

Fluorescence – a diamond’s tendency to produce a soft colored glow under ultraviolet light.

Girdle – the edge or narrow band between the upper and lower facets of a gem.  Widest part of a diamond.

Head – the part of the ring that holds the stone.

Inclusions – the identifying marks or flaws found inside or outside of the diamond.

Milgrain – is a decorating style creating a fine bead like effect on the top of the edge of a metal - is widely applied to the type of pavé setting that has edges surrounding the row of bead-set stones.

Pavilion – the lower part of the diamond below the girdle that comes to a point.

Polish – the finish or smooth surface of a diamond.  It can also mean the finish or surface of metals.

Semi-mount – a piece of jewelry that is set with side stones or accent gems, but without a center stone.

Setting – any ring before the stone is mounted.

Shank – the part of the ring that encircles the finger (does not include the head/setting).

Shape – the physical shape of the stone – ie: Round Brilliant, Marquise, Oval, Princess, Radiant, Emerald, Asscher, Cushion…

Symmetry – how perfect a diamond is cut – facets should be symmetrical.

Table – the flat facet of the upper most part of the diamond.

TW – total weight – the entire diamond weight of a piece of jewelry.