Diamond Dictionary

La Reine diamond. See queen of bel

(HUM DIAMOND.

Larkin's Flat. One of the early allu­vial diamond diggings on the Vaal River, Republic of South africa. La Rose Diamond. See la rose pink DIAMOND.

La Rose Pink Diamond. A 7.07-carat flawless marquise that was cut in 1954 and shown at the opening of the Sheridan Village Shopping Center in Peoria, Illinois, in March by Marks Bros. Jewelry Store. It was valued at $40,000. Alternate name is La Rose Diamond.

Lasarev Diamond. See orloff dia­mond.

laser. Acronym for Light Amplifica­tion by Stimulated Emission of Radia­tion. Lasers produce a special kind of light that is monochromatic, cohe­rent, and collimated. Laser systems have been used to enhance the clar­ity grade of Diamonds by providing passages to dark inclusions and to act as conduits for bleaching agents. See laser drilling.

laser drilling. Technique of enhanc­ing the clarity of a diamond by pro­viding access for bleaching agents to inclusions. Intense heat is generated by a focused laser beam which actu­ally burns into the diamond to or through an inclusion. Sometimes drilling a tiny hole (less than 5/ 1000ths of an inch in diameter) into a flaw may make it whiten and dis­appear. Usually, a special bleaching or leaching agent such as hydrofluoric acid is needed to leach out the dark inclusion. See laser.

Laser Gem. Trade name for a com­posite imitation (doublet) diamond simulant consisting of a synthetic spinel top and a strontium titanate bottom.

lasque. See bevel cut.

lasque diamonds. Very thin tabular diamonds which in the past were used by Indian cutters to glaze mini­ature paintings and hence were call­ed portrait stones or lasques.

Last Hope. A minor alluvial diamond deposit in the Barkly West area, Cape Province, Republic of South Af­rica. The output from this mine in one recent year amounted to less than 300 carats.

lax diamond. A seldom-used term for a diamond with little fire and bril­liancy.

laxey diamonds. Trade term for very shallow brilliant-cut diamonds.

lead glass. Glass containing a high percentage of lead. The addition of