Precious Coral vs Common Coral
In the gem and jewellery industry, the terminology that is used to designate the corals that are suitable for jewellery made in precious metals is different from the terminology used in biology. Biologists use the term "precious coral" for all the species that may be used as decoration, whereas CIBJO on the other hand has defined "precious coral" with more strict boundaries, distinguishing them from "common corals".
The word coral it self applies to thousands of marine species of the phylum Cnidaria, particularly those from the Antozoa class, including the subclasses Octocorallia and Hexacorallia. Of these, only a few are suitable for use in jewellery and decorative arts, hence the term "precious coral", a name that the trading community uses to distinguish them from the numerous species of common corals that are not traditionally used in jewellery. According to the CIBJO Coral Book, precious corals, notably red, pink and white varieties with porcelain-like luster after polishing, are limited to species belonging to the family Corallidae, particularly the Corallium, Pleurocorallium and Hemicorallium genera. Common corals are defined as calcareous type, usually found in coral reefs (e.g. sponge coral, bamboo coral and blue coral) or non-calcareous type (non-mineralized corals), with a soft organic skeleton, such as black and golden corals (e.g. Anthipathes spp., Kulamanamana haumeaae). One major difference between precious and common corals , specially reef corals, is the depth at which they grow andthrive.
Reef corals on coral reefs live in shallow waters, whereas precious corals live at greater depths and are harvested below 50 meters, some living down to 2000 meter deep. It is important to understand and clarify that corals used in the jewellery industry (precious corals) are not the same as the corals that live on coral reefs and which are threatened by climate change and ocean acidification.
THE ORIGIN OF CORAL FISHERY IN THE MEDITERRANEAN SEA
Precious coral fishery originated in the Mediterranean Sea, where its history can be traced back more than 2,000 years. According to Greek mythology, coral was born from the blood of the Gorgon Medusa, a vicious monster with a mass of snakes for hair and glittering eyes, so horrifying that anyone who looked upon her was instantly turned to stone.
After managing with the help of the gods to slay Medusa, the demigod Perseus was flying home with Medusa’s severed head in a magic bag when he looked down and saw the beautiful maiden Andromeda chained to a rockface, where she had been left as a sacrifice to a sea monster.
Alighting to save Andromeda, Perseus took Medusa’s head out of the bag and set it down upright on a bed of leaves and seaweed, which were instantly transformed into red coral. Alternatively, in another version of the story, the blood that dripped from the severed head turned into coral.
THE TRADE OF PRECIOUS CORALS IN THE MEDITERRANEAN FROM THE MIDDLE AGES TO THE NINETEENTH CENTURY LUISA PICCINNO
Throughout the Mediterranean, the cherished ancient traditions of coral fishing and processing have endured and developed through the ages. As early as the tenth to eleventh centuries, coral was already regularly fished along the coasts of North Africa, Spain, Provence and the Italian peninsula, as well as off the coasts of Corsica, Sardinia and Sicily. Mostly Italian and, to a lesser extent, French and Catalan fishermen were involved in these activities. In Italy, the Mediterranean red coral (Corallium rubrum) was fished and used to fashion rudimentary ornaments as early as the Neolithic age, as evidenced by artefacts found in Liguria and along the Adriatic coast. Even far from the sea, in the Alpine valleys, archaeologists have unearthed worked coral items from ancient burial sites (Segre Naldini 2019, 16– 21).
As far as coral trade in ancient times is concerned, according to some classical sources, the precious “red gold” was carried along the route that ran from Egypt via Cana (in southern Yemen) to Indian and Pakistani ports, where it was traded for fabrics and other precious goods sold by Chinese merchants (Iannello 2017, 111). Coral Fishery in the Middle Ages In the Mediterranean, from the late Middle Ages to the early modern age, coral was fished from small 10–16 ton vessels called coralline, each equipped with six to eight oars and a Latin sail. The crew on board was made up of a patronus—i.e. the captain, and often also the owner of the vessel—and from seven to eleven sailors, responsible for different tasks. Each boat was usually equipped with two dredges, one placed at the stern and one at the bow. The dredge (ingegno or ordigno) consisted of two large wooden beams tied together to form a cross, with a weight in the middle to sink it and one or more side nets. Long hemp ropes were used to lower the dredge down to the sea floor, at a depth ranging between 50 and 100 arms (about 24–48 m). The sailors would then raise the sail and follow the wind direction— or use the oars when there was no wind—to drag the nets along the sea floor until they were full enough. By jointly moving the boat and working the winch, they did their best to position the nets in such a way as to tear off as much coral as possible.
A similar manoeuvre was necessary to haul the nets back up again. In the Mediterranean, coral was harvested from the end of winter to the beginning of autumn. However, in some fishing grounds, such as along the coasts of North Africa and particularly in the waters surrounding the island of Tabarka in Tunisia, coral was harvested non-stop throughout the year. The boats generally moved in small fleets of 30–40 units accompanied by one or two guard boats. Once a fortnight, or sometimes only once a month, they would return to shore to stock up on supplies and deliver their coral harvest (Figs. 1.2 and 1.7). The Ligurians were undoubtedly ahead of all the other Italian populations dedicated to fishing and processing this precious product, not only from a chronological point of view but also in terms of their highly skilled workforce. Their investment in capital, men and other resources for these activities was such as to be compared to a “transhumance of the sea” (Grendi 1982, 445). Their coral fisheries expanded to extend from the Maghreb coast to Corsica, Sardinia and, to a lesser extent, the Tyrrhenian coast. This wide coral fishing area was consolidated during the early modern age when they were granted exclusive rights to exploit the rich coral banks growing in these areas. In particular, the King of Tunis granted them a monopoly on coral fishery in the waters of Marsacares in 1462. In 1475, abundant coral beds were discovered in Corsica, at that time ruled by the Republic of Genoa.
In 1543, the first agreement was signed under which the Spanish King Charles V granted some Genoese nobles the right to set up a permanent settlement on the Tunisian island of Tabarka and the monopoly to fish coral in its surrounding waters. The Genoese enjoyed this exclusive right for about two centuries. In its heyday, the Mediterranean coral fleet is estimated to have numbered about 300 Ligurian boats and over 3,000 men. For this reason, during the long spring and summer fishing seasons, there would be a dramatic increase in the populations of the small coastal villages of Liguria from where the coralline set sail. This happened regularly in the western Ligurian Riviera, from which, at the beginning of the seventeenth century, about 2,000 people are estimated to have sailed every year to reach the coral fisheries in Sardinia (Doneddu 2002, 199–210). 14 Chapter Three Genoa, Centre of Coral Processing and Trade The art of coral processing was probably initiated in the thirteenth century and further developed in Genoa from the second half of the fifteenth century, spurred by the growing supply of raw material available.
In 1477, forty-two coral masters and merchants applied to the city authorities of Genoa to formally establish their own guild governed by special chapters since they still had no statute like the guilds of other trades. It wasn’t until 1492, however, that the “Capitula artis coraliorum” (Chapters of the art of coral) were finally approved. These were regulations applicable to a guild of coral craftsmen—the so-called Corallieri—aimed at governing the work of its members, who numbered about seventy at the time, and protecting their monopoly (Pastine 1933, 279–281). The connection between coral fishermen and the craft of the Corallieri was governed by provisions issued by the government of the Republic of Genoa, which were reinforced several times between the sixteenth and seventeenth centuries. The provisions were designed both to ensure the exclusive supply of raw material to Genoese craftsmen and to keep their skills and production capacity within the city boundaries (Pastine 1933, 353–355). However, not all the raw coral reached Genoa. For example, most of the coral harvested in Corsican waters by employees of the Genoese nobleman Francesco Di Negro and his partners at the end of the sixteenth century was sent directly to Marseille. From here, this precious cargo continued its journey aboard French ships bound for Alexandria, where it was traded for equally expensive cargoes of spices (i.e., pepper, cinnamon, ginger, cloves, nutmeg, etc.) (Piccinno 2006, 121–124). The characteristics and intrinsic value of the harvested product varied, depending on the fishing ground. Sardinian coral was of medium size and good quality, while the coral from the Gulf of Naples was lighter in colour, yellowish, and therefore less costly: its price was about half that of Sardinian coral. Spanish coral and that from the Barbary Coast was dark red in colour and of medium size, hence of good quality and a similar price to Sardinian coral (Ghidiglia 1892, 486). The art of coral working enjoyed its heyday in Genoa in the sixteenth century before strong competition emerged from nearby Livorno.
During this period, Genoese merchants were dominating international finance by leveraging the huge fortunes they had made from lending money to the Spanish Crown, thus triggering what is called “the century of the Genoese”. They would combine banking with multi-sectoral investments, which often included the control of coral fishing and trade. The case of the Lomellini family and their centuries-old control of the island of Tabarka is the most striking example of a system involving many members of Genoa's aristocracy (Piccinno 2008).
Coral Use and Art in Europe Most of the coral processed in Genoa was sold in the local and European markets, although a significant percentage was sent to Livorno for further shipment to Far Eastern markets, where it was traded for jewels and other valuable products, such as diamonds and pearls (Rollandi 2017–2018, 360). In the Genoese market, coral was used as an ornament only by the working or middle class, as shown in the painting La Cuoca by Genoese artist Bernardo Strozzi (Fig. 3.1) (Orlando and Sanguineti 2019). It is no coincidence that the painting depicts a cook and not a noblewoman. On the other hand, while the use of coral in jewellery was generally limited in pre-industrial times, at least in Europe, it was extensively employed to produce sacred objects and other artefacts designed to embellish courts all over Europe. One of the most significant examples was the huge supply of processed corals from Genoa purchased on several occasions by the court of Ferdinand II of Habsburg, Count of Tyrol, between 1577 and 1590. This included outstanding coral artefacts, now part of the collection of Ambras Castle, kept in the Kunstkammer of the Kunsthistorisches Museum in Vienna. A Triumph of Galatea (Figs. 3.2 and 3.3) is one of them, allegedly crafted by Filippo Santacroce, a master from Urbino who worked in Genoa for many years. Members of the Doria family would commission highly precious items from him, fashioned in rare materials such as precious woods, ivory and coral. This particular work features a symbolic mythological diorama enriched with mother-of-pearl shells and coral figures depicting legendary characters and sea monsters. It is dominated by an image of Christ crucified on a coral branch atop an undersea hill of Golgotha.
According to an inventory of Santacroce's workshop made in 1607, the artist’s works were essentially small in size—rarely bigger than the palm of one’s hand—and consisted of sacred icons, images of Christ on the cross and the Virgin Mary, cameos, and amulets. The same Viennese collection includes another highly valuable work, also attributed to Genoese artisans, which dates from the end of the sixteenth century. It is a writing box in sterling silver adorned with a carved coral branch depicting Neptune riding a dragon (Fig. 3.4). The deity holds a shield in his left hand, while in his right hand he was most probably holding a trident, now lost (Del Mare 2014, 3).
THE SCIACCA RED CORAL STORY
In the Mediterranean Sea, the Sicily Channel, about 145 kilometres wide, is a sizeable tectonic structure extending in a NW–SE direction along the northern margin of the African promontory. It was produced in the collision, still ongoing, between the African and European plates (Capaccioni et al. 2011) and shaped by two independent tectonic processes that acted simultaneously and overlapped each other: the Maghrebides-Apennines accretionary prism and the Sicily Channel rift (Corti et al. 2006). This area has long been one of the most famous red coral fishing grounds of the entire Mediterranean basin (CattaneoVietti et al. 2016, 2017), also hosting the deepest population ever found, down to depths of 1,016 metres around the Maltese Islands (Costantini et al. 2010; Knittweis et al. 2016).
In particular, between 1978 and 1981, exploitation of the Skerki banks, 50 nautical miles (nm) south of Marettimo Island, yielded significant amounts of red coral, fished at depths of 40–50 metres. Above all, the Sicily Channel hides one of the greatest mysteries in the natural and geologic history of the Mediterranean Sea, an unprecedented submerged treasure whose origin remains unclear: namely, large sub-fossil red coral banks at depths ranging from 150 to 200 metres off Sciacca, a small town in the south of Sicily (Fig. 4.1). Fig. 4.1 Overview of Sciacca village and harbour in the late 19th century. Giuseppe Rajola Collection. 22 Chapter Four The Discovery of the Sciacca Coral In May 1875, a local fisherman named Alberto Maniscalco, known as Bertu Ammareddu, and his colleagues Giuseppe Muschidda and Alberto Occhidilampa were fishing with long-lines about 16 nm off Capo San Marco when they discovered the first bank, 2.5 nautical miles long and 2 nautical miles wide, at 37°20'3" N and 12°48'7" E (Mazzarelli 1915a,b).
While the fishermen of Sciacca had a long tradition of anchovy and sardine fishery, they knew nothing about red coral. So they decided to go and see some fishing crews from Torre del Greco (Naples) who were coral fishing in the nearby Trapani area. When the fishermen of Torre del Greco (Fig. 4.2) heard about the Sciacca bank they rushed to the site, well aware of its economic potential (Rajola 2012). Fig. 4.2 Torre del Greco harbour in 1908 with a corallina, the typical boat for coral fishing, in the foreground. Giuseppe Rajola Collection.
In the following years, two other deposits were discovered, on August 1878 and January 1880, at 37°14'7" N; 12°43'3" E (24 nm off Sciacca) and 37°5' N; 12°36'3" E (33 nm off Sciacca), respectively. These findings were exceptional in terms of the amount of coral involved and they caused a real “coral rush” that lasted 30 years (Rajola 2012). It was immediately apparent that the coral branches were dead, since they were lying in thick mounds on a flat, muddy sea floor (Fig. 4.3). To collect them, the local fishermen therefore modified the typical “Italian bar”, a sturdy five-metre-long metal or wooden bar with bundles of nets attached beneath, usually employed by professional coral fishermen on hard grounds. In the case of Sciacca, it was not necessary to remove the colonies from rocks, so the codata (long tail)—a new, very efficient tool, better suited to the small local fishing boats and the bottom morphology—was adopted. This equipment consisted of a 200-metre-long rope with bundles of old nets attached at regular 1.5 metre intervals to entangle the coral branches (Gangemi 2011, 2014).
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