Coral has been used for personal ornamentation, and as an article of commerce, from the earliest period recorded in writing. Popular to-day, as it has almost always been--especially in the form of polished fragments, pierced and strung like beads, and less extensively in beads, spherical or oval--the most desired, high grade of light rose-pink coral is becoming scarce, and those who gather it from the ocean's floor are anxiously seeking new sources of supply. At the present time coral is increasing in favour and the demand for it is steadily growing.
Coral--like the sea gem, the pearl,--is essentially carbonate of lime. Its structure is erected by a family of zoophytes, gelatinous marine animals (not insects as is too often written) called polyps. The coral is secreted by a peculiar layer of the skin; it is the calcareous skeleton of the lowly organised animal, and gradually develops like the bones of vertebrates, and is not built up as bees build a honeycomb as is popularly believed. The pits or depressions on a branch of coral represent the places where the coral colonists once grew. Coral is a common submarine feature in low latitudes all around the globe, but the gem or precious coral, Corallium rubrum, formerly called Corallium nobile, comes almost exclusively from the Mediterranean Sea off the African, Corsican, and Sicilian coasts. A wild-rose pink is the particular shade most highly favoured. The Corallium rubrum, the only species utilised and valued to any extent for jewelry, belongs to the family Gorgonidae of the group Alcyonaria.
The skeleton of a colony of Corallium rubrum is found to be cemented firmly by a disc-shaped foot to any dense natural or foreign object on the sea bottom, as a stone, cannon-ball, bottle, or, as is recorded in one case of fact, a human skull. The branches seldom exceed a foot in length and an inch in diameter. A curious characteristic of coral is, that it grows always perpendicular, or approximately, at a right angle to the surface to which it is attached--downward, if its foothold is on the under face of a rock.
The colonies are usually from sixty to one hundred feet beneath the sea's surface.
Some expert authorities have fathered the assertion that about thirty years is required for coral stock to develop into full size; yet the Sicilian coral bank is divided into ten sections, one of which is finished every year, and at the end of the decade the first bank yields full-sized stock.
Pietro Moncadi of Palermo, said to be the largest dealer in Italian coral, during a recent visit to New York, reported that the demand for high grade red coral leads the supply. Many beds off the Italian coasts are exhausted and there is much prospecting off Malta, Malabar, and East African coasts, at great expense and, so far, with very small reward. Signor Moncadi made the statement that the United States buys the finest red coral, and the producers who possess the highest grade have to seek no other market.
The home of the coral industry is Italy, where there are about sixty work shops, with about six thousand employees. Torre del Greco is the centre of both the coral-fishing and the coral-working industries. The coral-workers pierce and string pieces of coral of all shapes and sizes. The beads are spherical or egg-shaped--the latter are called "olives." The handicraft of the Italian coral-workers includes carving of a high artistic order--the forms representing many natural objects--and the cutting of beautiful cameos. The coral-gatherers employ fine distinction in denominating coral tints. Pure white is bianco, fresh pale flesh-red is pelle de angelo; pale rose, rosa pallido; bright rose, rosa vivo; these choicest tints are followed by "second colour," secondo coloro; red, rosso; dark red, rosso scuro; and, darkest of all reds carbonetto or ariscuro.
The specific gravity of precious coral is 2.6 to 2.7; hardness in Mohs's scale about 3-4. Coral is soft enough to be easily worked with a file, edged tools, and on a lathe; it is too soft to take a high polish, but despite that dissimilarity from the precious stones of whose company it is a popular member, its fine colour sustains its claim to beauty, and it highly deserves inclusion in a book of gems.
But little coral, comparatively, is mounted in Italy, the setting being done in the fashion in demand in the country where it appears in the jewelry trade.
In the Orient coral is always in demand, with India in the lead followed by China and then Persia. The Chinese mandarins sometimes pay incredible sums for exceptionally fine coral buttons for their caps.
Pieces of coral are used for rich and costly handles of parasols and umbrellas; the coral handle of an umbrella belonging to the Queen of Italy being valued at nearly two thousand dollars. A coral necklace exhibited in 1880 at the International Fisheries Exhibition held at Berlin, was valued at nearly twenty-nine thousand dollars. In Italy the superstition that the wearing of coral is a protection against the evil eye, accounts for its appearance as the commonest personal ornament among the masses; similarly, it is in evidence among the lower class of Italians in the United States. Coral is easily imitated, however, and most of the defences thus relied upon by superstitious wearers are spurious, but equal to the genuine in efficacy. Red gypsum is a common sophistication for precious coral, and simple tests are: scratching it with the finger nail and the application of acid, under which it does not, like genuine coral, effervesce. Celluloid is now sometimes used as a substitute for coral.
The existence of coral within the United States, on the shores of Little Traverse Bay, at Petoskey, Michigan, should not escape mention in an American book. The coral found here is fossil, and many specimens possess rare structural beauty; they are compact and susceptible to a high polish. The fragments found are water-worn, and the weight of some masses secured attained to three pounds. The colour is grey, of various shades. Local lapidaries cut and polish these handsome fossil relics of a prehistoric submarine period, and shape them into seals, charms, cuff buttons, and paper weights. In the mineralogical section of the reports on the Eleventh Census, 1900, Mr. George Frederick Kunz records that from $4000 to $5000 worth annually were sold.
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Precious Stones Guide Vol 4
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