Glossary of Pearl Terms L
L-grade: Letter grade assigned to low-grade pearls by Japan?s Pearl Inspection Offices from 1952 to 1998.
La Paz pearls: Natural pearls from Central America.
lacquer coating: Temporary coating applied to some imitation and cultured pearls to enhance their color and luster.
Lake Biwa: Located northeast of Kyoto, Lake Biwa is Japan?s largest freshwater lake and site of that country?s first freshwater pearl culture operations, headed by Dr. Masao Fujita.
Lake Kasumigaura: Located northeast of Tokyo, Lake Kasumigaura is Japan?s second largest freshwater lake and origin of Kasumigaura (Kasumi, Kasumiga) pearls.
Lamprotula leai: Freshwater mussel native to China. The mussel is a source of bead nuclei but is not used in pearl culture.
lantern baskets: Baskets used to hold young mollusks when suspended from lines during saltwater pearl culture. Method is most often used for akoya mollusks for a short period after they are bred in hatcheries.
laser treatment: Supposed method of modifying a cultured pearl?s color. It is often claimed but does not actually exist.
Latendresse, John: (July 26th, 1925?July 23, 2000) A pioneer of freshwater pearl culture in the United States.
lead nuclei: Used by Mikimoto in his early attempts at akoya pearl culture. The attempts failed.
liang: Historical weight unit used to valuate pearls in China. One liang equals 1/10 or 1/16 jin. One jin equals 500 grams.
lianzhu: Historical Chinese quality factor that described the finest quality natural pearls.
ligament pearl: Defunct trade term once used to describe a natural pearl formed within the mantle isthmus, just below the ligament.
light pearl: One of four Saxony quality levels used to describe natural German river pearls. A light pearl was of the finest quality. See also: half-light pearl (high quality), sand and rotten pearl (the lowest qualities).
Linn?, Carl von: (May 13, 1707?January 10, 1778) Also known as Carolus Linnaeus. In 1758 he originated the binomial system of zoological taxonomy that has been used since. He was the first person to culture whole pearls.
lion?s paw pearls: Non-nacreous scallop pearls that exhibit white, pink, violet and/or orange colors.
Little Willie: Discovered by Bill Abernethy in Scotland in 1967. This natural freshwater pearl is round, meaures 11.6 mm and weighs 34 grains (8.5 carats). Same as Abernethy Pearl.
longline systems: Horizontal lines stretched between buoys and anchored to the bottom at both ends. Chaplets (vertical lines) with baskets or net panels of nucleated mollusks are suspended underwater from the longlines.
luli: Ancient Roman imitation pearls made from glass with a coating of silver and another layer of glass.
luster: Quantity and quality of light reflected from the surface or just under the surface of a natural or cultured pearl.