Damascene: Refers to a type of jewelry that today most often comes from Spain; the jewelry is inlaid or engraved with gold or silver metals and black enamel; originated in the 14th century in Damascus, hence the name.
Demi-Parure: A partial set of jewelry. A full set usually includes a necklace, earrings, bracelet and brooch, all matching. A demi ("demi" is the French word for half) can refer to any combination such a necklace and brooch, or bracelet and earrings, but is lacking the other pieces of a full set
Deposé: The rights or patent granted for an exclusive jewelry design in France. If the reverse of a piece of jewelry is stamped "deposé" it was made in France. The literal translation is "hand made".
Diamond: A mineral composed essentially of carbon that crystallizes in the cubic, or isometric, crystal system and is therefore singly refractive. It is by far the hardest of all known natural substances (10 on Mohs’ scale); only manmade Borazon and synthetic diamond are as hard. In its transparent form it is the most cherished and among the most highly valued gemstones. It occurs in colors ranging from colorless to yellow, brown, orange, green, blue, and violet. Reddish stones are known, but those of an intense red color approaching that of ruby are excessively rare. Its hardness and high refractive index (2.417) permits it to be fashioned as the most brilliant of all gems, and its dispersion (.044) produces a high degree of fire. The specific gravity is 3.52. Sources include various sections of south, west, southwest and middle Africa; Russia; central, east and northeast South America; India; Borneo; and Australia. It is also found in the United States, but not in commercial quantity.
Diamond Cut: A name sometimes used in the colored-stone trade for brilliant cut.
Dog Collar: Popular during the Victorian era, this was a snug necklace made either of rows of pearls or beads and usually worn high up on the neck. Ribbons were also used with a jewel or pendant hanging at the front. It was made popular in the late Victorian and Edwardian periods by Queen Alexandra who had a long, graceful neck.
Duette: A combination of two clips on a pin back. Duette was a registered design by Coro, but is now used generically for this design