Glossary of Pearl Terms A
abalone blister pearl: Nacreous natural half-pearl formed on the inside of an abalone shell.
abalone cultured blister pearl: Nacreous pearl cultured by attaching a half-round nucleus to the inside of the abalone shell. At harvest, the shell is cut around the blister, leaving the nucleus and shell intact.
abalone mabe pearl: Nacreous cultured blister pearl that is separated from the shell at harvest. Its half-round nucleus is removed, the cavity is filled with epoxy resin and backed with a mother-of-pearl disk.
abalone pearl: Nacreous natural whole pearl formed in the body of an abalone.
abas: Unit of weight historically used in Persia to valuate natural pearls. One abas is equivalent to 0.91 carat.
Abernethy Pearl: Discovered by Bill Abernethy in Scotland in 1967. This natural freshwater pearl weighs 44 grains.
abyadh: Historical Persian quality factor for the best color natural pearl (white color).
acid test: Method of testing the authenticity of a natural or cultured pearl with hydrochloric acid. This destructive test is often used by pawnbrokers.
adductor: The muscle that opens and closes a bivalve mollusk?s two shells; it is sometimes cooked, eaten and considered a delicacy.
Ago Bay, Japan: The location of the Mikimoto?s first pearl farm and still the home of many akoya farms today.
akoya: The Japanese name (akoya-gai) of the Pinctada fucata martensi mollusk used in cultured akoya pearl production.
akoya keshi: Small pearl found in the akoya mollusk where it forms as a byproduct of the pearl culturing process.
akoya pearls: Natural or cultured pearl from an akoya mollusk.
alabaster pearl: Imitation pearl made from an alabaster bead that is coated with iridescent lacquer.
ama: The historical female pearl divers of Japan. There were two types: the kachido (those who worked alone) and the funado (those who worked with a partner from a boat, typically the husband).
Amami Gold Pearl: Pearl first produced by the Tasaki Shinju Company in the Pinctada maxima mollusk on the Ryukyu Islands of Japan; known for its better-than-average luster.
American pearls: Natural pearls found and cultured pearls grown in the waters in and around the Americas.
aniline dyes: Synthetic organic (contain carbon) agent used to artificially produce dark colors in cultured pearls.
Antilles pearls: Imitation pearls made from the spindle of trochus or turbo shells.
aragonite: Calcium carbonate crystals stacked in a brick-like pattern; a component of nacre and mother-of-pearl.
atlas pearl: Imitation pearl made from atlas spar.
atoll: A ring of coral that nearly or wholly encircles a lagoon. Atolls are considered the best place to farm cultured pearls in the Pinctada margaritifera mollusk.
Atrina pearls: Dark pearl produced by Atrina vexillum in the Gulf of California.
awabi pearls: Japanese abalone pearl found in the gastropod Auris marina.