GENERAL CHARACTERISTICS OF PEARLS AND SHELLS FROM THE VARIOUS FISHERIES
Arabian Sea.—Pearls have fine orient, but the color inclines to yellow.
Shells are larger than those of Ceylon but of little value for mother-of-pearl: iridescent, black-edge m. of p.; known as Lingahs.
Aroe.—Pearls usually good orient; many of irregular shape.
Shells are of medium size, black-edge and iridescent.
Auckland.—Pearls white, but not remarkable for luster.
Shells, medium size, black-edge m. of p.
Australia.—Pearls of Australia generally are of good color, but not as lustrous as those of other sections.
Shells usually large and heavy and the nacre is white.
Bandas.—Pearls good.
Shells are small but heavy and good; black to greenish edge nacre.
Ceylon.—Pearls average finest in the world for orient and color.
Shells, small and valueless for m. of p.
Costa Rica.—Pearls good average.
Shells, medium size, greenish yellow edge.
Egyptian (Red Sea).—Pearls good but run yellow.
Shells, medium size and nacre has greenish edge.
Fiji.—Practically the same as the Bandas.
Gambier.—Pearls good, many fancy colors.
Shells, large, fine nacre with very black edge.
Haiti.—Pearls fine, shells good.
Manilla.—(Includes Batjan, Bima, Ceram, Salawatti, Sooloo, etc.) Pearls, good color and orient.
Shells, large, good, yellow edge nacre.
Merguian Archipelago.—Pearls and shells similar to the Manillas.
Mexico and Panama.—Pearls fair; blacks, grays and fancy colors often fine.
Shells, medium size: nacre has greenish edge.
South Sea Islands.—Pearls usually fine.
Shells generally large, heavy and fine black edge m. of p.
Venezuela.—Pearls, good luster and color—many fine baroques.
Shells: small, beautifully iridescent, but valueless.
Pearls.
| Hardness, 3.5-4 | Sp. Gr., 1.59-1.62 |
Composition.
| Carbonate of Lime | 91.72 | ||
| Organic matter | 5.94 | ||
| Water | 2.34 |