Dog Brooch Set with Lapis, Coral and Onyx by Mauboussin Paris, Numbered 2342.

Coral is classified as an organic gemstone, separate from the larger mineral category, meaning that it is derived from animal or plant life, a group which also includes pearls and amber.  More specifically coral is a ‘calcareous concretion’, and is in actuality the skeleton of the sea animal coral, composed of calcium carbonate.  There are many types of corals, but the varieties used in jewellery typically form in warm salt water including the Mediterranean Sea, the Red Sea, and the waters of Asia, Australia and the Caribbean.

Coral has long been associated with protective powers, and particularly in Mediterranean cultures was believe to ward off the evil eye.  For this reason it was often used in children’s jewellery as well as toys, such as rattles and teething devices.   It was also thought to banish tension and fear, and to promote positive social interactions.  Still today in Italy it is common to see ‘cornicello’ pendants made of polished segments of red coral. 

The coral used in jewellery is typically red, pale pink, or peach, but it also forms in white, black, brown and, though quite rare, in blue. Usually it is polished to a shine, however peach coral is often left matte, and is known in the trade, rather charmingly, as ‘angel skin’.  In any shade, it is a lovely and apropos summertime gemstone.

The house of Mauboussin was founded in Paris in 1827 by M. Rocher in collaboration with Jean–Baptiste Noury.  Throughout the nineteenth century the firm exhibited in numerous World Expositions, including the 1873 Vienna Exposition and the 1878 Paris Exposition, winning a medal in the latter.  In 1925 Mauboussin won the Grand Prix at the Exposition des Arts Décoratifs, considered by some to be the birthplace of the Art Deco style.   The house of Mauboussin continued to produce innovated jewels through the twentieth century, opening their flagship at the famed Place Vêndome in Paris in 1955.  Throughout their existence, their elite clientele has run the gamut from moguls to movie stars.

Chalcedony is a form of quartz with a very special structure, known in gemmological circles as cryptocrystalline—meaning the crystal structure is incredibly small and dense, rendering it one of the smoothest gemstones.  This allows for the material to be crisply carved, which makes it perfect for the jeweller type for which it is best known—cameos and intaglios.

Chalcedony also comes in a myriad of colours and patterns, and is often better known by these sub-types.  One is onyx, a black form of chalcedony, often with white banding.  Another is agate, which has fine layers of colour, and was thought by ancient peoples to quench thirst, and protect against fever.  One of the most popular is sardonyx, characterized by wider, straight banding, which makes it perfect for use in cameo carving. Bloodstone is deep green colour with red splashes.  Carnelian is the name for the reddish orange variety, while jasper is the name of chalcedony of any other colour or pattern.