A religious image often that of a saint, painted on a wooden panel. The word comes from Greek word eikon meaning likeness.

International Gemological Institute. The largest independent institution that certifies gems and appraises diamonds.

An art movement originating in France in the 1860s, the main artists concerned being Cezanne, Degas, Monet, Morisot, Camille Pissaro, Renoir and Sisley. They were concerned with representing day-to-day existence in a realistic way, recording the fleeting effects of light and movement. Their usual subjects were landscapes or social scenes.

A thin, veil of paint, or paint-tinted size, applied to a ground to lessen the ground's absorbency or to tint the ground to a middle value.

The natural birthmarks inside a stone that can affect its flow of light and also add uniqueness and character. Inclusions vary in size, shape, quantity, position and color.

A black ink originally from China and Japan, consisting of finely divided carbon suspended in a solution of gum, glue or varnish.

A portion of the metal setting has been cut away and replaced by a stone. In this setting, the stones are flush with the metal surface.

The cutting into a stone or other material or the etching or engraving on a metal plate of an image. The opposite of relief. Intaglio printing techniques include engraving and etching.

The purity and brightness of a colour. Also called saturation.

An international organization that independently certifies diamonds as to their quality and authenticity.

Several stones are mounted together by metal under the stones. The metal cannot be seen from above, making the stones appear as if they have no setting at all.