Sir Joshua Reynolds' Chalcedony Sealstone
18th century

Tradescant Room
Gallery 27, First Floor


Focus on the Object

About the Object
This new acquisition is a pendant seal of a seated female figure by Edward Burch. It was once owned by Sir Joshua Reynolds who wore it attached to his watch and used it to seal his letters.

Seal-stones & Gem Engraving
The 18th century experienced a revival in gem-engraving, partly due to a greater interest in the arts of Antiquity. Rome was the major centre for gem-engraving, but in the second half of the 18th century London became the most important production centre outside Italy.

This seal-stone is in the form of an intaglio, in which the image is engraved on a gemstone so that the design is sunk beneath the surface of the stone. Once engraved, the stone was simply mounted into a ring or a fob and used for sealing. When the wax seal is impressed, the resulting image stands proud.

The stone used here is a type of quartz, called chalcedony. In 1812 an Austrian mineralogist, Friedrich Mohs, developed a 10-point scale of hardness for such minerals: 1 for talc, 10 for diamond. True hardstones, like quartz, are 6/7 on the scale. Chalcedony came in a number of varieties, such as ‘common’ (light-coloured) chalcedony, cornelian and bloodstone (dark green with small red deposits). For particularly rich patrons, some engravers would execute their work on incredibly hard stones, reputedly even diamond.


The source for the seated female figure seen here is taken from a marble sculpture of Winter by Etienne-Maurice Falconet. Joshua Reynolds had a plaster cast of a small terracotta model version and commissioned Burch to make an engraved copy of it as his seal. The original shows a seated female figure sheltering flowers from the destruction of Winter under her long skirt.