Poets like to use the metaphor of the pearl to describe the perfect beauty of a woman. So it is not surprising that people already decorated themselves with pearls some 6000 years ago. The "precious stones of the sea" always attached a strong symbolic effect. They combined happiness, wisdom, dignity, wealth, and power with them, so they were, above all, in the possession of the rulers of this world. In many European countries, there were laws that allowed the wearing of pearls to the nobility. Well-known witnesses of this period are La Regente, originally owned by Napoleon I and now one of the largest and most expensive pearls in the world, or La Peregrina from the 16th century, which came from the Spanish royal house through detours to Richard Burton, who in turn invited Liz Taylor as a gift.
Pearls are formed in the interior of mussel shells in warm marine waters, on the other side of the equator, more rarely also in freshwater muddles. We owe it to a natural defensive reaction of these softeners: the outer skin of the shell (epithelium), which normally secures mother-of-pearl and thus is responsible for the construction of the mussel shell, also envelops foreign bodies that have penetrated between shell shell and mantle. This creates a pearl bag, in which the pearl is finally formed. Like pearl, the bead consists mainly of carbonic lime (aragonite), the microcrystals of which are stored in concentric layers, and are conjugated by an organic horny substance, the conchyn. This compound is so strong that pearls, despite their low Mohs hardness of 2.5 to 4.5, are extremely strong and elastic - a pearl falling to the ground springs like a rubber ball undamaged without damage.
One differentiates between "real pearls" (Oriental pearls), which have been produced without human intervention, and cultivated pearls, which also naturally grow, but with the development of the man a bit aids. In doing so, it introduces small particles from the mantle tissue of a gland shell into another shell in order to stimulate them to produce pearls. As with real pearls, this tissue part is first surrounded by the pearl bag and then surrounded by concentric mother-of-pearl layers. A ball-shaped polished, polished mother-of-pearl core is often used, which decisively influences the later shape of the bead. This "operation" requires great skill and is dominated by only a few experts worldwide.
After the operation, the mussels are put back into their natural environment in bamboo cages or nets and are nurtured for 2 to 6 years until the pearls can be harvested. This principle was already known in China of the 13th century, where small Buddha figures were placed in shells, in order to create mother-of-pearl Buddha beads. However, with the commercial production of cultured pearls, the Japanese Kokichi Mikomoto began to appear in the early 1920s. Today there are breeding farms in marine waters around Japan, Australia and South and Southeast Asia as well as in some freshwater lakes. Because of the great rarity of the oriental pearls are now practically only cultured pearls in the trade.
Well-known seawater cultured pearls are the Akoyaperle from the Japanese and Chinese sea, the anthracite to black Tahitiperle and the silvery-white to gold-colored South Sea pearl, which, in relatively large mussels, often reaches a considerable extent and therefore as "queen of cultured pearls". A random product of the Perlenzucht is the Keshi pearl - it is created, if the inserted mother-of-pearl is repelled by the mussel and instead only the coat-tissue-particle of mother-of-pearl is enclosed. These pearls are usually irregularly shaped (baroque pearls), but have a beautiful shine. The most important freshwater pearl is the biwa-pearl, which was originally bred in the Japanese Lake Biwa, but now comes from China.
Since natural and cultured pearls are formed in a similar manner and are similar in appearance, they are difficult to distinguish. Investigations with UV or X-ray beams reveal the thickness of the pearl shell and the inner structure: the natural pearl is composed entirely of concentrically arranged mother-of-pearl layers, whereas the different structure of the core is clearly visible in the cultured pearl. Only natural pearls may be referred to as "pearls", pearl beads must always be recognizable by a name addition.
The beads are given form, color and luster by nature, they do not need further processing. The most protected are large spherical beads with the typical pearl luster, the coveted slander. The weight of beads is usually expressed in grains (1 grain = 0.05 g = 0.25 carats), increasingly also in carats. Its value can only be determined by a specialist: It multiplies the weight of the bead in grains with itself and the thus determined "Mal weight" again with the so-called "Malzahl", which results from the quality of the bead and other factors, eg the Just actual color gradients. Two pairs of pearls, owned by Jacques Cartier, must have been of great value. In 1916 he paid his famous shop on New York's 5th Avenue.