A 9ct gold intaglio seal; base set with an incised onyx. Height…

 

onyx. Onyx is a form of agate. European onyx is generally green, but can be many other colours, and can contain bands of black and/or white.

This multicoloured stone is widely used for table tops, lamp bases and in jewellery. Some types of onyx are also used for cameos of which the upper white layer is cut away to reveal the colour beneath.

intaglio. A term used to define a method of decoration most common in glassmaking and jewellery which involves engraving, carving or moulding an image into the background, leaving an impression, and leaving the top surface of the item flat, the opposite to relief carving, and also know as counter-relief.

incised. A record of a name, date or inscription, or a decoration scratched into a surface, usually of a glass or ceramic item with a blunt instrument to make a coarse indentation. Compare with engraving where the surface is cut with a sharp instrument such as a metal needle or rotating tool to achieve a fine indentation.

The buyers premium is an additional percentage charge on the hammer price of the item, imposed by the auction house to cover administrative costs. The buyers premium percentage varies between auction houses, with a range of 12.5% to 22%.