Coral is one of the oldest gem materials used by man and has been used decoratively by the populations that border the Mediterranean since ancient times. It was viewed as a thing of beauty, as well as having both powerful spiritual and medicinal properties, and the Romans made necklaces of Coral which a child would wear around their neck to protect them from illness and danger.
In 77 AD Pliny wrote about it in one of the first Encyclopaedias, Naturalis Historia, he describes the most valuable Coral as the reddest and most branch-like. This red Coral grows typically in dark environments with low sedimentation, either in caves and crevices, or in the depths of the sea. The original prized species, Coralium Rubrum is found almost exclusively in the Mediterranean. It grows at depths of up to 300m below sea level, the shallower habitats having been depleted by over the centuries by harvesting. In the underwater caves of Alghero in Sardinia it grows at depths of 4 to 35m. The same species is also found at the Straits of Gibraltar, and the Cape Verde Islands, and other Corallium species are native to the western Pacific.
Italy, and in particular Naples is known for the quality and beauty of their Red Coral jewels, and these became a favoured souvenir of Grand Tourists and many examples of Coral jewellery found their way back to England. Pompei and Vesuvius were considered an essential stop on ‘the tour’, and Torre del Greco, the centre of Coral jewellery making, was close by. In the 18th Century, the Kingdom of Naples established the Real Compagnia del Corallo in Torre del Greco, and around the same time Coral was recognised as being an animal, not a plant, which was a theory that had been put forward almost a millennium earlier by Persian scholar Abu Al-Biruni (973 – 1048). It was only after Jean Andre Peysonnel’s published research paper in 1726 that this theory was finally accepted.
‘Since 1400 Torre del Greco has been known as a centre for specialists devoted to the art of coral fishing. Its famous fishermen were so adept at their craft that they ventured as far as the African coasts with their small boats called “coralline”….. The convenience of locating the working and selling of coral in Torre del Greco itself where the raw material was easily available did not go unnoticed as in 1790 the “Royal Coral Company” was established, which granted people from Torre a monopoly on their precious “red gold”.’ Antonio de Simone.
With the advent of the European Grand Tour, which became de rigeur for the rich during the Georgian and Victorian eras for the upper classes, many examples of coral jewellery found their way back to England. Pompei and Vesuvius were considered an essential stop on ‘the tour’, and Torre del Greco, the home of the Compagnia del Corallo, and the centre of coral jewellery making, was close by.
We have several pieces in our collection which feature this wonderful brightly coloured Precious Red Coral and likely originate from Italy.
Precious Coral is the name used to distinguish the Coral used in jewellery from the numerous species other species of common Coral. Precious Corals, notably red, pink and white, that exhibit a porcelain like lustre after being polished, are limited to those belonging to the family Corallidae, in particular the Corallium, Pleurocorallium and Hemicorallium genres. Common Corals are reef Corals, which are shallow water Corals, whereas Precious Corals live at depths of up to 2000m and are harvested at depths of over 50m.
These are not the Corals that are threatened by climate change and of the 7000 plus species of corals of all types, only a handful are used in jewellery. Coral traders refer to the corals by their commercial names, which vary by geographical origin and local custom. Making the distinction between precious Coral and, say, dyed common Coral or Coral imitation is not normally difficult for an experienced Gemologist or trader.
PRECIOUS CORAL VARIETIES
SARDINIAN or MEDITERRANEAN
Corallium Rubrum, the most sought after and popular variety of precious coral. It is uniform red with a deep saturation, and is the coral that was used almost exclusively to embellish historical and religious artefacts. This bush shaped coral has an average height of 15cm and a weight of 100g. The area around the Sardinian town of Alghero is known as the Coral Riviera. The deep red Coral harvested from caves close to the town historically used to be known as the Blood of Medusa, and is mentioned in documents as far back as 700 AD.
This is a variation of Corallium Rubrum found (from around 1875) near the town of Sciacca in Sicily, and is orange and pink in colour. It used to be found off the coast of Sciacca in Sicily, and was collected from sediment, but stocks are currently depleted. It’s also found off the coast of southern Spain, Malta and Sardinia. The output from Sciacca is estimated at around 14,000 tonnes, and had a great impact on the coral industry.
AKA, MORO, OXBLOOD
A very dark, red Coral with a white interior. A fan shaped coral with an average height of 20cm and a weight of 200g. It lives at depths of 80 – 300m in Japanese waters. The dark red oxblood beads or cabochons made from this Coral, especially in larger sizes, are among the most sought after worldwide. Aka means red in Japanese.
MOMO, CERASUOLO, SATSUMA
Pleurocorallium Elatius or Corallium Elatius, and is the largest type of precious Coral. This Coral comes in shades from bright red, through salmon pink, to flesh coloured, again with a white interior. It’s also a fan shaped Coral with an average height of 35cm. Its Latin name is Momo means peach in Japanese.
ANGEL SKIN, BOKE, MAGAI
A rare variety, Pleurocorallium Elatius is found in varying shades of flesh pink, and is harvested in the waters around Japan and Taiwan, from a depth of 150m to 300m. A fan shaped Coral with an average height of 35cm this pale pink Coral has many aficionados in the high end jewellery market, and is the most popular after the traditional Mediterranean red.
PURE WHITE or SHIRO
Pleurocorallium Konojoi is typically milky white, sometimes with red or pink specks. It originates in the waters around Vietnam and Hainan, and is a fan shaped Coral of a similar size and shape to Momo/Boke, but with a white colour. It grows at a depth of 80m to 300m. Shiro is Japanese for white.
MIDWAY, ROSATO or WHITE/PINK
Pleurocorallium Secundum, from the waters around Hawaii and Midway in the Pacific, is found at the extreme depths of 400m – 600m. This fan shaped Coral is often clear pink, but also comes in veined white or pink varieties, sometimes with red specks. It has an average height of 25cm.
DEEP SEA or SHINKAI
Known as Hemicorallium Laquense or Corallium Secundum and also from Midway, north west of Emperor Seamont. The colour of this Coral is somewhere between bright white and pink, and is decorated with reddish veins or spots. It is found at a depth of anything between 1000m and 2000m, with an average height of 30cm.
Hemicorallium Regale. Harvesting of this Coral ceased in the 1980’s due to the high costs. It is pomegranate in colour with different shades of uniform pink. Its characteristic colour gives it the name “garnet”. It comes from Hawaiian waters from a depth of 350m to 600m and is a parallel shaped oral with an average height of 15cm.
MISU, MISSU or MISS
Hemicorallium Sulcatum is uniformly coloured on the spectrum between violet and pink, and is found in the waters north of the Phillippines, Taiwan, and Japan. It’s a long shaped coral lives at depths of 100m to 300m, with an average height of 25cm.
CURRENT LAWS ON CORAL
There are many processes used to change the appearance of precious coral, but the only one that is allowed is polishing the surface using a colourless agent like paraffin wax. Then it is still classed as untreated coral.
The supply chain for precious Coral – from fishing and harvesting through trading and fashioning – is now regulated and protected, in many cases by national law as well as by wildlife conservation organisations. It is currently legal to buy and trade all red Coral (Corallium Rubrum), be it antique or new. Precious Black Coral (not all Black Coral is precious) is banned for export by many countries. Reef building or ‘stony’ Corals, are not used in the course of jewellery making, with one exception – the Blue Coral. All Precious Corals come from deep water, Reef Corals are shallow water. Faux coral is made from crushed or powdered Coral glued together with a polymer, and then shaped. Because these products can use any bit of Coral, it may very well be that they are made from smaller, younger Corals, which have not had a chance to develop, putting at risk the survival of the industry. Although not illegal, it is probably best to avoid.
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