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 perfectly spherical form, the price can hardly be stated with exactness. Such a pearl is perhaps worth £10 if it weigh 1 carat, four times as much if it weigh 2 carats, and eight times as much if it weigh 4 carats. Button-pearls, which have one side convex and the other flat, are less valuable than round pearls, but pear-shaped pearls often fetch more. The large irregular and grotesque pearls called baroque acquire value when set into curious figures—busts, dragons, griffins, fruits, etc.—by the aid of gold and enamel mountings. Fantastic arrangements of this kind exercised the skill of many 16th and 17th century jewellers, but the artistic merit of these productions cannot be appraised very highly; the chief excuse for their existence must be sought in the difficulty of making any other use of the misshapen pearls in question. The Green Vaults of Dresden are rich in specimens of this sort. It should be mentioned that the majority of pearls used in ordinary jewellery are half-pearls, that is pearls sawn in half. Seed pearls, the small pearls attached as pendants to jewels, the pearls sewn on garments, and necklace pearls, are perforated by careful drilling

Pearls have been used in almost all parts of the world, and from very early times, for jewellery and personal adornment. The pearls set in antique Roman ornaments have rarely survived intact to the present day. Sometimes the place of a pearl in the setting is represented by a small brownish residue; sometimes the reduced form of the pearl is still to be seen, deprived of much of its lustre by the long-continued action of water charged with carbonic and vegetable solvent acids from the earth.

The use of coral in jewellery justifies us in adding a few words here concerning this product of animal origin. All the white, pink and red coral used for objects of personal adornment is derived from a single species, Corallium nobile, belonging to the sub-class