|A. E. Köchert
Birks & Sons
Black, Starr & Frost
Carl Wagner and Frédéric-Jules Rudolphi
John Rubel Co.
Marcus & Co.
Mellerio dits Meller
Oscar Heyman & Bros
Tiffany & Co.
Van Cleef & Arpels
Unlike other gems, pearls are produced by living animals and require no human faceting or shaping to expose their natural beauty.
Natural pearls are formed when some irritant becomes lodged in the shell of certain mollusk. In response to the irritation, the mollusk secretes nacre (mother-of-pearl) which gradually builds up in layers around the irritant to form a pearl, after several year.
Pearls have been attributed great powers and incorporated into the mythology of virtually every culture which has encountered them. They have, as far as 2300 BC in China, always been symbols of wealth, prestige or love and especially cherished by Royal families of all origins.
Their value is determined by a combination of the luster, color, size, lack of surface flaw and symmetry. Among those attributes, luster is the most important differentiator of pearl quality. All factors being equal, however, the larger the pearl the more valuable it is. Large, perfectly round pearls are rare and highly valued.