|
Where Do Natural Pearls Come From?Where do natural pearls come from? Now you can speak with authority about where certain species of mollusks are found.
Where do natural pearls come from?
Since pearly concretions partake of the characteristics of the shell within which they are formed, it follows that practically all species of mollusks whose shells have a well-developed nacreous lining yield pearls to a greater or less extent. But the number of these species is relatively small. They belong chiefly to the Margaritiferae, or pearl-oyster family of the sea, and to the Unionidae, or family of fresh-water mussels. Pearls occur also in some univalves, but not so abundantly as in bivalves of the families mentioned. Broadly stated, we may hope to find pearls within any mollusk whose shell possesses a nacreous surface; and it is useless to search for them in shells whose interior is dull and opaque, such as the edible oyster for instance.
The great bulk of the pearls on the market, and likewise those of the highest quality, are from the Margaritiferae, which are widely distributed about tropical waters. Although these mollusks are spoken of as pearl-oysters, they are not related in any way to the edible oysters (Ostrea) of America and Europe. Where do natural pearls come from?Commercially considered, the pearl-oysters are roughly divisible into two groups, (1) those fished exclusively for the pearls which they contain, and (2) those whose shells are so thick as to give them sufficient value to warrant their capture independently of the yield of pearls. The best examples of the first group are the pearl-oysters of Ceylon and of Venezuela, and to a less extent those of the Persian Gulf, the coast of Japan, and of Sharks Bay, on the Australian coast. Of the second group, the pearl-oysters of Torres Straits and of the Malay Archipelago are the most prominent members. Between these two groups are the many species and varieties whose shells and pearls are more evenly divided with respect to value, including those of Mexico, Panama, the Red Sea, the South Sea islands, etc. Where do natural pearls come from?The greatest pearl-producer in the family of pearl-oysters is the Margaritifera vulgaris of the Gulf of Manaar and the Persian Gulf, and to a much less extent of the Red Sea. It occurs in various other inshore waters of the Indian Ocean, and about the Malay Archipelago and the coast of Australia and New Guinea, although it is not the principal pearl-oyster of those waters. This species is quite small, averaging two and a half inches in diameter in Ceylon waters, and somewhat more in the Persian Gulf. Where do natural pearls come from?Ranking next to Margaritifera vulgaris in extent of pearl-production is the Margaritifera margaritifera, which is widely distributed about the tropical inshore waters of the Pacific and Indian oceans. Several varieties of Margaritifera margaritifera are recognized. The type species occurs along the north coast of Australia, from Brisbane on the east to Sharks Bay on the west; on the New Guinea coast; at Formosa; and about many of the island of the Pacific. The well-known "black-lip shell" of Australian waters is of this species; it shows a greenish black on the margin of the nacre. The yield of this is very small compared with that of the large pearl-oyster of Australia. Where do natural pearls come from?Since 1870, the largest pearls have been found mainly in a very large species of pearl-oyster, Margaritifera maxima, obtained off the north and west coasts of Australia, among the Sulu Islands, and elsewhere in the Malay Archipelago. Where do natural pearls come from?There are numerous other species of pearl-oysters, but they are of slight economic importance. Pearls are yielded by various species of Unionidae or Naiades occurring in the rivers of America, Scotland, Saxony, Bavaria, Norway, Sweden, Russia, France, China, etc. These mollusks exist exclusively in the fresh-water streams, lakes, and ponds, and quickly die when submerged in salt water. The Unionidae are of particular interest in America, as it is here that this group is most abundant, and nearly every stream east of the Rocky Mountains contains more or less of them. Where do natural pearls come from?The Mississippi basin abounds in Unios, or "clams," as they are known to the fishermen of that region, and furnishes about 400 of the 1,000 recognized species of this important family. The Unios are most abundant in clear, running water, where the bottom is gravelly or sandy. The interiors of the shells are iridescent, and vary greatly in tint, exhibiting many delicate shades of color from silvery white to straw color, pink, purple, and brown. Where do natural pearls come from?About five hundred species of American fresh-water mussels have been recognized by conchologists. Most of these species have common names which fishermen use, such as "niggerhead," "three-ridges," (yields most number of pearls) "bullhead," "sand shells," "buckhorn," "butterfly," and "pancake". The rivers of Europe, and of Asia also, contain numbers of pearl-bearing mussels. The principal pearl-bearer of Europe is the Unio margaritifera. In Great Britain it is known as the pearl-mussel; in France as the moule or huitre perliere; in Germany as perlenmuschel; in Belgium as perlmussla; in Russia as schemtschuschuaja rakavina, and in Finland as simpsuckan cuosi. The Unio margaritifera likewise exists in Siberia and possibly elsewhere in Asia. Other species of Unio exist there and in Mongolia, Manchuria, etc., as, for instance, U. mongolicus, U. dahuricus, etc. A leading species in eastern China, the Dipasas plicatus, has long been extensively employed in the artificial production of pearly objects or culture-pearls. Where do natural pearls come from?
A few pearls are also obtained from the sea-wings or wing-shells (Pinna) the silkworms of the sea, found in the Red Sea, the Mediterranean Sea, the Indian Ocean, the southern coast of America and elsewhere. The window-glass shell (Placuna placenta), the vitre chinoise of some writers, yields a few small, irregularly shaped pearls of a dull leaden color. It occurs in the inshore waters of the Indian and the southwestern Pacific oceans; fisheries are prosecuted in Tablegram Lake, near Trincomali, on the northeast coast of Ceylon; on the coast of Borneo, especially at Pados Bay. Where do natural pearls come from?The giant clam (Tridacna gigas) of tropical waters yields a few large opal-white symmetrical pearls, with a faint luster and of little value. The oval shell is found in tropical seas, and especially in the Indian Ocean. Pearls of slight luster also occur in the quahog, or had clam (Venus mercenaria), of the Atlantic and Pacific coasts of the United States. Where do natural pearls come from?Shelly concretions are found in the edible oyster of America (Ostrea virginica), as well as in that of Europe (O.edulis); but these are commonly objects of personal interest or of local curiosity, rather than of artistic or commercial value, as they are lacking in luster and iridescence. Where do natural pearls come from?Among univalves, the most prominent pearl-producer is probably the common conch or great conch (Stombus gigas) of the West Indies and the Florida coast, which secretes beautiful pink pearls of considerable value. The ear-shells or abalones (Haliotidae) found on the coast of California, Japan, New Zealand, and other localities in the Pacific, secrete pearly concretions, sometimes with fine luster. Abalone pearls are especially interesting on account of their brilliant an unusual colors. Where do natural pearls come from?Similar concretions are found in species of turbos and turbinella, especially the Indian chank (Turbinella rapa), which yields pink and pale red pearls. The pearly nautilus (Nautilus pompilius) yields a few yellowish pearls, especially those taken in Australian waters. Where do natural pearls come from?The Raganighantu of Narahari, a Kashmir physician of about 1240 A.D., reported pearls as coming form bamboos, coconuts, heads of elephants, bears, serpents, whales, fish, etc.; although it conceded that these were deficient in luster, which is recognized as the characteristic feature of pearls. It is understood, therefore, that this use of the word signifies only hard concretions of spherical form. Where do natural pearls come from? Information from Kunz and Stevenson in 1908.
Free Ezine: "All Things Pearl!"
|
