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La Reine Diamond La Rose Pink Diamond Lasarev DiamondLaser Gem lax diamond laxey diamonds PDF Print E-mail
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Friday, 21 September 2007

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

Last Updated ( Thursday, 01 November 2007 )
 
La Belle Helene Diamond Lace La Favorite Diamond Lake George diamond lapidary PDF Print E-mail
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Friday, 21 September 2007

La Belle Helene diamond. An ex­ceptionally fine 160-carat alluvial diamond. Found on the Orange River, Republic of South africa in 1951. Bought by Romi Goldmuntz of Antwerp for £80,000 and named for his wife. Cut in the U.S. into three stones: matching pear shapes of 30.28 and 29.71 carats and a 10.50-carat marquise. All were sold pri­vately.

Lace (or Crown) Mine. A diamond mine of minor importance located about 100 miles south of Johannes­burg in the Kroonstad district, Orange Free State, Republic of South Africa.

La Favorite Diamond. A top-quality 50.28-carat stone. Exhibited at Chi­cago World's Fair in 1934, when it was owned by a Persian and val­ued at $1,000,000. Present location unknown.

Lake George diamond. Same as Her­kimer diamond.

lambreu. A Brazilian term for irregu­lar diamond fragments.

Landak River. A source of early diamond deposits on the Island of

Kalimantan, formerly called Borneo.

See KALIMANTAN.

lap. A flat, horizontal, diamond-dust-impregnated cast-iron wheel, 12 to 18 inches in diameter, that re­volves about a vertical shaft. It is used for grindingpolishing facets on Diamonds. Another name is scaife (also spelled skeif or skaif). Diamond-charged laps, often made of other materials, are also used for industrial purposes and for fashion­ing colored stones. (See photo.) and

lapidary (or lapidist). A cutter, grind­er and polisher of colored stones. In the trade a lapidary is not necessarily an engraver of gems, this being con­sidered a specialized art. A cutter and polisher of diamonds is classed as a diamond cutter, as distinguished from a gem cutter, or lapidary.

lapper. See blocker.

lapping. See blocking.

La Reine des Beiges Diamond. A

50-carat diamond. Thought to have been owned by the Queen of Bel-


gium in the latter part of nineteenth century. Existence not verified; how­ever, it is believed to be an alternate name for the Queen of Belgium Dia­mond.

 
kraal Krandall Diamond Kromellenboog. Kruger Diamond PDF Print E-mail
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Friday, 21 September 2007

kraal. A South African (Boer) word for a hut or group of huts for housing native diamond miners.

Krandall Diamond. A 40-carat gold­en yellow cushion-cut diamond own­ed by Sidney Krandall, a Detroit jew­eler. Reported to have been in the collection of Catherine the Great. It has an unusual cut of 114 facets of which 56 are on the girdle. The Krandall was originally bought by Mr. Krandall's father about 1934 from the London dealer, Oyster Ovid.

Kromellenboog. A minor alluvial diamond deposit in the Christiana area, Transvaal Province, Republic of South africa. Production from this digging is miniscule.


Kruger Diamond. A South African statesman and one-time president of the Transvaal, Stephanus Johannes Paulus (Paul) Kruger (1825-1904), was honored when he was presented with a 200-carat alluvial diamond that was given his name. The stone is said to have changed hands fre­quently and to have belonged suc­cessively to several powerful native chiefs. After its last chief-owner had been taken captive, Kruger freed him. In gratitude, the chief sent the diamond to his benefactor as a gift.


The whereabouts of this stone is not known today.

Krupp Diamond. The 33.19-carat, emerald-cut Krupp Diamond was once part of the estate of Vera Krupp, ex-wife of the German munition maker and industrialist. In 1968, it was sold at auction by Parke-Bernet for $305,000 to Richard Burton for his wife, Elizabeth Taylor.

Kt. An abbreviation for karat.

Kurupung River. A river in Guyana along which are located alluvial diamond deposits.

Last Updated ( Friday, 05 October 2007 )
 
Kohlville Diamond Kollur Diamond Koppiesfontein mine Koppiesvlei Kott-Dar-EI-Kouti PDF Print E-mail
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Friday, 21 September 2007

Kohlville diamond. See theresa

DIAMOND.

Kollur Diamond. A 63-carat di­amond that is said to have been bought by Tavernier in 1653 at In­dia's Kollur Mines. Additional details lacking.

Kollur Mines. A group of old diamond mines in the Golconda district, India. The famous Orloff Diamond is thought to have been found in this region. See golconda,

INDIA, HYDERABAD.

Komsomolsky Diamond. A large named rough diamond crystal, weight unknown, in the Russian Diamond Fund, Moscow.

Kono District. An important di­amond-producing region in Sierra Leone, africa. See sierra leone.z

kopje (kop"-ee). A South African word of Dutch origin meaning hil­lock. Some diamond pipes were marked by small elevations above the surrounding terrain; such mounds were known locally as kopjes. The term is now used to mean a knot on the surface of a diamond. See knot.

kopje walloper. A slang term that was used to describe a diamond dealer or a buyer of rough Diamonds in the early days of the South African diamond fields.

Koppiesfontein mine. A small di­amond pipe mine in the Jagersfon-tein area, Orange Free State, Repub­lic of South Africa.


Koppiesvlei. A minor alluvial dia­mond deposit in the Schweizer Ren-eke area, Transvaal Province, Repub­lic of South Africa. This deposit contributes very little to total South African production. Koslow I & II. These two diamonds were reportedly cut from a rough of unknown size. The Koslow I was sold after cutting and no further in­formation is known about it. The Koslow II was reported to be "of the finest quality, in the best proportions of a pear cut," and weighed 20 carats. It was owned in 1961 by the firm of the late Nat Koslow of New York City. No other information is available.

Kott-Dar-EI-Kouti. Diamond-mining areas along the Kotto River in the Central African Republic.

Koyle's Kopje (kop"-ee). A small diamond pipe mine in the Kimberley area, Cape Province, Republic of South Africa.

 
POLYSYNTHETIC TWINNING Koh-i-Noor Diamond. PDF Print E-mail
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Friday, 21 September 2007

knot lines. A term used by some cut­ters for the twinning lines on or within a diamond. See twinning lines,

POLYSYNTHETIC TWINNING, REPEATED TWINNING,

Koffiefontein Mine (kof'-ee-fon-tane"). The third largest diamond pipe mine in the Republic of South africa and one of the earliest dis­coveries in the Orange Free State. Formerly an important producer, it was operated until 1931. The mine was reopened after 40 years in Au­gust 1971 to operate as an open cast mine for 10 years, after which time underground mining will commence. It is located between the Kimberley and Jagersfontein Mines.

Koh-i-Noor Diamond. The known facts about the Koh-i-Noor date back to the year 1304, when it was owned by the rajah of the huge territory in India known as Malwa, which today is divided into Indore, Ghopal and Gwalior. Two centuries later, it fell into the hands of Sultan Baber, the first of the Mogul emperors. Through his son, it passed down the line to all the great Moguls, including Shah Jehan, who built the Taj Mahal as a memorial for his beloved Queen, Mumtaz. During this period, there


was a belief that "he who owns the Koh-i-Noor rules the world." In 1739, Persia's Nadir Shah invaded India, captured Delhi and, after a systematic pillage of the city, seized the diamond. According to one ac­count, the stone was one of the eyes in the peacock in the Peacock Throne that Shah Jehan began and Aurangzeb, his son, completed and that Nadir Shah carried off, thus gaining possession of the jewel. Another story is that the conquered Mogul ruler, Mohammed Shah, had hidden it inside his turban, which he never removed. When Nadir Shah discovered this, he took advantage of an Oriental custom and invited his victim to a feast, suggesting that they exchange turbans. The vanquished ruler dared not refuse and Nadir Shah, retiring with the turban, unroll­ed its yards of silk and released the magnificent gem, which fell to the floor. It is then that he is supposed to have cried, "Koh-i-Noor!" (meaning "mountain of light"); thus the stone was named. The Koh-i-Noor went back to Persia with Nadir Shah but was again in India in the jewel chamber of Lahore, capital of the Punjab, when that state was annexed to the British Empire. In 1849, the stone was taken by the East India Co. of England as partial indemnity after the Sikh Wars in the Punjab. It was presented to Queen Victoria in 1850 at a great reception in St. James Palace, to mark the two hundred fif­tieth anniversary of the founding of the East India Co. by Queen Elizabeth I. When displayed at the Crystal Palace Exposition in London in 1851, viewers were disappointed that it did not exhibit more fire; therefore, Victoria decided to have it recut. A Mr. Voorsanger, the ablest diamond cutter of Amsterdam's famed Coster plant, came to London for this. A four-horsepower steam engine was set up in the workshop of the Crown Jewelers, to drive the wheel. Prince Albert placed the stone on the mill and the Duke of Wellington started the wheel. The cutting required 38 days, which was considered a miracle, since the Re­gent had required two years to cut. The operation cost $40,000, and the Koh-i-Noor was reduced from its former 186-carat old-Indian cut to a 108.93-carat oval brilliant. Be­fore cutting, it had been valued at $700,000. Queen Victoria, by the wish of her subjects, wore the big diamond in a brooch; this perhaps gave rise to the superstition that only queens, not kings, could wear it safely. Victoria willed it to her daughter-in-law, Queen Alexandra, who wore it at her coronation. A new crown was made for the late Queen Mary in 1911, with the Koh-i-Noor as the central ornament. In 1937, it was transferred to the Queen Mother's Crown. Without the royal arches, the Queen Mother continues to wear the circlet of the Crown,

 
Klipfontein Klippan GIRDLE THICKNESS PDF Print E-mail
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Friday, 21 September 2007

Klipfontein. A small alluvial di­amond deposit in the Bloemhof area, Transvaal Province, Republic of South africa. Production for one re­cent year was approximately 350 carats.

Klipkuil. A minor alluvial diamond deposit in the Lichtenburg area, Transvaal Province, Republic of South Africa. Approximately 600 carats were recovered in one recent year.

Klippan. A minor alluvial diamond deposit in the Lichtenburg area, Transvaal Province, Republic of South Africa. The yearly production from this mine is very small.

knife-edge girdle. A girdle of a diamond that is so thin that it can be likened to the edge of a sharp knife. Since such a girdle is easily chipped,


a well cut girdle has an appreciable thickness to withstand damage. See

GIRDLE THICKNESS, LUMPY GIRDLE.

Knoop Indentation Hardness Test. A

technique for measuring the hard­ness of metals, alloys and other materials. The hardness is deter­mined by pressing a pyramid-shaped diamond into the material to be tested and computing the area of the indentation in relation to the load on the diamond point.See mohs scale.

knot. (1) A term applied to an in-;luded crystal of diamond that is ariented differently from the host crystal and is encountered during the fashioning process. Knots stand out

 
Kleinzee Mine Klipdrift Klipfontein knife-edge girdle PDF Print E-mail
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Friday, 21 September 2007

Kleinzee Mine. An alluvial diamond mine in Namaqualand, formerly op­erated by De Beers Consolidated Mines, Ltd. This deposit is no longer producing. See namaqualand.


Klipbankfontein. A minor alluvial diamond deposit in the Lichtenburg area, Transvaal Province, Republic of South africa. Production for one re­cent year was under 100 carats.

Klipdam. A minor alluvial diamond deposit in the Barkly West area, Cape Province, Republic of South Af­rica. The 220-carat Burgess Diamond was found at Klipdam in 1907.

Klipdrift. One of the early alluvial diamond diggings on the Vaal River, Cape Province, Republic of South Af­rica, and the site of the first diamond discoveries in 1869. In this area 14 mines were discovered in ensuing years. This group, about 20 to 40 miles northwest of Kimberley, is now known as the Barkly West Group. Present-day production is very low; in one recent year, for example, ap­proximately 300 carats were recov­ered.

Klipfontein. A small alluvial di­amond deposit in the Bloemhof area, Transvaal Province, Republic of South Africa. Production for one re­cent year was approximately 350 carats.

Klipkuil. A minor alluvial diamond deposit in the Lichtenburg area, Transvaal Province, Republic of South Africa. Approximately 600 carats were recovered in one recent year.

Klippan. A minor alluvial diamond deposit in the Lichtenburg area, Transvaal Province, Republic of South Africa. The yearly production from this mine is very small.

knife-edge girdle. A girdle of a diamond that is so thin that it can be likened to the edge of a sharp knife. Since such a girdle is easily chipped,


a well cut girdle has an appreciable thickness to withstand damage. See

GIRDLE THICKNESS, LUMPY GIRDLE.

Knoop Indentation Hardness Test. A

technique for measuring the hard­ness of metals, alloys and other materials. The hardness is deter­mined by pressing a pyramid-shaped diamond into the material to be tested and computing the area of the indentation in relation to the load on the diamond point.See mohs scale.

 
Kimberlite Diamond-Mining Kimberlite Gem King of Portugal Diamond Kissidougou PDF Print E-mail
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Friday, 21 September 2007

Kimberlite diamond-Mining Co.

One of the companies that was or­ganized to mine the Arkansas dia­mond deposits. See Arkansas.

Kimberlite Gem. A trade name for synthetic rutile.

King Charles I Seal Diamond. Said to be a carving of the Royal Arms of England. Weight unknown. Prior to his death in 1649, Charles I gave the stone to his son Charles II, who needed money during his exile. The latter is thought to have sold it to Tavernier, the French jeweler and traveler, who in turn, disposed of it in Persia (Iran). Present whereabouts unknown. In 1966 this diamond was not listed among the Crown Jewels of Iran.

King Cut (trademark). A rarely used modification of the standard 58-facet brilliant cut. It possesses the usual ar­rangement for a brilliant but has a twelvefold symmetry, instead of eightfold (i.e., 12 star facets, 12 bezel facets, etc.), with a total of 86 facets.


King of Portugal Diamond. See

BRAGANZA DIAMOND.

Kirsten, F. B. A De Beers employee who discovered, in 1896, that dia­monds in concentrate were non-


wettable and stuck to grease, while all the other minerals were washed over the grease. G. F. Labram, chief engineer of the company, was the first to take advantage of Kirsten's discovery. He invented a sloping table with five steps covered with grease which trapped dia­monds. A stream of water carrying concentrates was passed over the grease table; the Diamonds stuck to the grease and the other material continued over the trap.

Kissidougou. See kerouane.

Kistna Group. A name sometimes used to refer to the ancie'nt alluvial diamond deposits near the historical city of Golconda, State of Hydera­bad, India. See golconda, Hyderabad,

INDIA.

kite cut. A four-sided form of cutting, usually step cut, that resembles a child's kite in outline.


kite facets. An alternate term for the eight main bezel facets, the outlines of which resemble a kite. See bezel facets.

 
Kimberley Mine kimberlite PDF Print E-mail
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Friday, 21 September 2007

Kimberley Mine. July, 1871, is the usually accepted date for the discov­ery of Diamonds at Colesberg Kopje on the farm Vooruitzigt, Cape Pro­vince, Republic of South africa. This first discovery was originally known as De Beers New Rush and later shortened to New Rush; finally, it was named Kimberley, in honor of the then British Secretary for the Colonies. Before its closing in 1914, it produced 14,504,566 carats of diamonds (equivalent to three tons), valued at £Big Hole, is the largest man-made hole in the world. The total depth of the mine is 3610 feet. The crater itself is 1300 feet deep and the depth of the water is approximately 700 feet, rising at the rate of 12 feet per year. The dis­tance across the mine, from north to south, is 1550 feet; from east to west, 1500 feet. The perimeter is one mile and the area is 38 acres. During its period of operation, 25 million tons of earth were excavated. 47,139,842. The Kimber­ley Mine, known as the

Kimberley Mines. A term used to des­ignate a group of five diamond pipe mines in the vicinity of Kimberley, Republic of South Africa: Bultfon-tein, De Beers, Dutoitspan, Kimber­ley and Wesselton. This group of mines is often classified as the De Beers Mines, because they are all under the control of De Beers Con­solidated Mines, Ltd. Another name sometimes used for them is the Big Five.

kimberlite. The name applied to the type of mafic igneous rock (a serpen-tinized phlogopite-peridotite) that is the host rock of diamonds in all primary diamond deposits discov-
Last Updated ( Thursday, 01 November 2007 )
 
Kaokoveld Kaplan, Lazare Kapuas River PDF Print E-mail
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Friday, 21 September 2007

Kaokoveld. An area along the coast of South-West africa, extending from the border of Angola south to the concessions of diamond Mining & Utility (S.W.A.), Ltd. De Beers Con­solidated Mines, Ltd. has three con­cessions in the Kaokoveld that are being worked or prospected under the supervision of Consolidated Diamond Mines of South-West Af­rica, Ltd. See south-west africa.

Kaplan, Lazare (1883- ). Lazare Kaplan is one of the diamond indus­try's great cleavers and master cutters. Born in Russia, Kaplan was appren­ticed at his uncle's diamond cutting plant in Antwerp, at the age of 15. At 22 he became the head of his own cleaving enterprise and introduced many innovations such as using India ink on the diamond in theplanning and cutting stages. In 1914, Kaplan set up shop in New York and in 1917, established a diamond cut­ting and polishing factory in Ponce, Puerto Rico, using an assembly line method. In 1933, he was asked by Harry Winston to cut the Pohl Dia­mond a large 287-carat stone with many inclusions. This turned out so successfully that when Winston pur­chased the 726-carat jonker Dia­mond, he commissioned Kaplan to cut it. Kaplan studied the jonker for over a year and prepared a cutting plan that was totally different from that provided by European experts; he used a novel combination of saw­ing and cleaving to obtain better shapes and greater yield. Before be­ginning the cutting process, Kaplan predicted the dimensions and weights of the anticipated gems. Even though some of the stones were completely concealed in the rough diamond, his prediction was exact; the jonker Diamond was divided into 12 beautiful, flawless gems with a remarkable yield of over 51%. Kap­lan demonstrated for the first time that diamond has six secondary dodecahedral cleavages as well as four octahedral cleavages. He was the originator of a scientific grading system for Diamonds which required uniformity in "make" with grading based on color and clarity standards. At 93, he still is active as the Chair­man of the Board of Lazare Kaplan International and continues to apply his enthusiasm and skills to planning the cutting of difficult stones.

Kapuas River. A source of early diamond deposits in the Kalimantan province of Borneo, Republic of In­donesia. See INDONESIA, REPUBLIC OF.

 
kalette Kalimantan Kameelkui PDF Print E-mail
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Friday, 21 September 2007

kalette. German equivalent for the word culet.

Kalimantan. A province on the island of Borneo, Republic of Indonesia, that is a source of Diamonds. See In­donesia, REPUBLIC OF.

Kalkfontein Mine (kalk'-fon-tane").

A small diamond mine in the town of Jagersfontein, Orange Free State, Re­public of South africa.

Kameelkuil. A minor alluvial dia­mond deposit in the Schweizer Ren-eke area, Transvaal Province, Repub­lic of South Africa. Production figures for one 12-month period in a recent year showed a yield of only 173 carats.

Kamfersdam Mine (kam"-fers-dam'). A diamond mine located a few miles north of Kimberley, Cape

 
Kaalpan Kaaipiaats Kaal Valley Diamond Mine Kafferpan PDF Print E-mail
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Friday, 21 September 2007

K. An abbreviation for karat. Kaalfontein Mine (Kal'-fonn-tane").

A small diamond mine in the Orange Free State, Republic of South africa. It was discovered in 1898.

Kaalpan. An alluvial diamond dig­ging in the Bloemhof area, Transvaal Province, Republic of South Africa, the annual production of which is negligible.

Kaaipiaats. A minor alluvial diamond deposit in the Vereeniging area, Trans­vaal Province, Republic of South Af­rica. The annual yield from this dig­ging is of little consequence.

Kaal Valley Diamond Mine. A small mine located in the Orange Free State, South Africa; it is no longer being worked.

Kaapse Tijd (The Cape Period). An old Dutch phrase referring to the late 19th century, when the discovery of Diamonds in South Africa stimulated the cutting industry in Amsterdam.

Kafferpan. The name of an alluvial diamond deposit in the Bloemhof area, Transvaal Province, Republic of South Africa, the annual production of which is negligible.

Kahama pipes. Three small dia­mond-bearing kimberlite pipes about 75 miles west of Mwadui, Tanzania.

Kalahari Desert. A desert region of southwestern Africa covering about 20,000 square miles between the Orange and the Zambesi Rivers and from longitude 26°E. nearly to the At­lantic Ocean. This great, relatively infertile area lies in Botswana, a part


of the Republic of South Africa and eastern South-West Africa, and is a part of the remarkably flat huge inner tableland of South Africa. The area is covered generally with an overbur­den of red-colored soft sand. De Beers prospecting units used indi­cator minerals such as pyrope and ilmenite brought to the surface by ants and traced river bed samples upstream to locate kimberlite pipes in Botswana. The first pipe discov­ered in Botswana in 1965 was not diamond bearing. However, in 1968, De Beers located a number of new kimberlite pipes, some diamondifer-ous, in Botswana. These included the 2125AKI diamond pipe, in Orapa, which is about five times the size of the Finsch Mine in area.

 
Jubilee Diamond Institution 48.42-carat briolette-cut diamond PDF Print E-mail
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Friday, 21 September 2007

Jubilee diamond. A 245.35-carat, cushion-shaped, brilliant-cut dia­mond of unsurpassed color, clar­ity, brilliance and symmetry — a diamond so perfectly proportioned that it can be balanced on its culet, which is less than two millimeters in diameter! Such is the description of the world-renowned jubilee Dia­mond. South africa's famous Jagers-fontein Mine produced this cele­brated diamond crystal in 1895. It had an irregular shape, somewhat like a flattened octahedron, but without definite crystal faces. It was first known as the Reitz Diamond, in honor of President F. W. Reitz of the Orange Free State. The cutting of the stone took place in 1897 (the year of Queen Victoria's Diamond Jubilee, from which the stone derived its name). A 13.35-carat pear shape also was cut from the same crystal, but its ultimate disposition is unknown. The jubilee was exhibited at the Paris Ex­position of 1900, where it received world-wide attention and the high praise of gem experts. Shortly there­after, it was sold to Sir Dorab Tata, a Parsi of Bombay and the founder of the Indian iron-and-steel industry, who owned it until his death. (Note: A Pars/ is a person of Persian des­cent, usually an affluent and highly educated citizen of Bombay City and State, who is an adherent of the an­cient Persian religion called Zoroas-trianism.) In 1939, the executors of Tata's estate sold the stone through Cartier, Ltd., London, to Paul-Louis Weiller, a wealthy and well-known patron of the arts. Weiller lent the jubilee in 1960 to the Smithsonian

Institution, Washington, D.C., for an exhibit. In 1966, it was shown at the De Beers Diamond Pavilion in Jo­hannesburg. Rough weighed 650.80 cts.

Julius Pam Diamond. A 246-carat diamond found in the Jagersfontein Mine, Republic of South Africa, in 1889. It weighed 123 carats after cut­ting. The present location is un­known. It should not be confused with the Pam Diamond. June Briolette Diamond. The June Briolette is a pale, greenish-yellow


48.42-carat briolette-cut diamond. It is suspended in a pin formed of a wreath of oval, round and pear-shaped Diamonds of matching col­ors. Created and owned by Julius Cohen, New York City manufactur­ing jeweler, the jewel is valued by him at $140,000.

Juscelino Kubitschek Diamond. A

174-carat diamond that was found in the Municipality of Estrela do Sul, Minas Gerais, Brazil, in 1954. Addi­tional details are not known.


Last Updated ( Friday, 21 September 2007 )
 
Joblong River Jonker Diamond purchased by private gem collector PDF Print E-mail
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Friday, 21 September 2007

Joblong River. A river in Liberia, the gravels of which are a very minor source of alluvial Diamonds. See

LIBERIA.

Johannes Gem. A trade name for synthetic rutile.

Jonaskop. A minor alluvial diamond deposit in the Barkly West area, Cape Province, Republic of South Af­rica. The annual production for this digging is insignificant.

Jonker Diamond. In January, 1934, a 726-carat diamond was found on the property of Jacobus Jonker in an alluvial deposit on his farm at Elandsfontein near Pretoria, Republic of South africa. The stone was of unusually fine color and purity. It was purchased by the Diamond Pro­ducers' Association for $315,000 and was later sold to Harry Winston, New York City gem dealer, for a re­ported $700,000. The diamond was entrusted to Lazare Kaplan, master cutter, who produced a marquise and 11 emerald cuts from it. The Ma­harajah of Kapurthala bought two of the smaller diamonds for mount­ing in a ring; the other nine were


purchased by private gem collectors. The largest stone, called the jonker Diamond, was a 66-facet emerald cut that weighed 142.90 carats; it was recut in 1937 to 125.65 carats and 58 facets, to give it a more ob­long outline. The Jonker was sold to Farouk while he was still King of Egypt. After he went into exile in 1952, the location of the stone be­came a mystery. In 1959, however, there were rumors that Queen Ratna of Nepal was wearing it, and it has since been confirmed that the late Farouk did sell the great diamond to the little country in the Himalayas for a reputed $100,000. The jonker Diamond No. 4 was sold in October, 1975, to an unidentified South American at the Sotheby Parke-Bernet auction in New York City for $570,000. Reportedly, the jonker was sold in Hong Kong to an un­known businessman for $4,000,000 in 1974.


Journado diamond. A misnomer for a colorless imitation stone.

journaleiro. A Brazilian term used by native prospectors and miners to refer to a location where they feel sure of finding diamonds.

jubilee cut. A rarely used modifica­tion of the brilliant cut, in which the table and culet are replaced by ex­tended star facets and other modifi-


Jubilee cut

cations are made in other facets, making a total of 88 facets. It was named in commemoration of the 60th anniversary of Queen Victoria's accession in 1897.

 
jig jigger Joao Neto de Campos PDF Print E-mail
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Friday, 21 September 2007

jig. A mechanical sieve used to sepa­rate Diamonds and other heavy mate­rials from lighter, worthless material. It is constructed of two compart­ments and filled with water. In one compartment a plunger works up and down. In the other compartment is a screen mounted several inches below the level of the water. The screen is covered with heavy gravel of a size too large to pass through the meshes. As the plunger moves up and down it produces a like move-


ment in the water in the pulsator. The water, as it moves up in the screen compartment, lifts the gravel and the concentrate that has been fed in with it and then drops it. Thus the heavy material is able to work its way through the large gravel and fall through the screen into the bottom of the box. The lighter material is un­able to penetrate the mass of gravel, and is pushed along by the incoming water and concentrate until it is forced over the edge of the jig and taken to the tailings heap. The mate­rial that falls to the bottom includes the diamonds and other heavy min­erals. Also called pulsator jig. Note: jig largely replaced by heavy-media cone separators.

jigger. A workman who sorts or cleans ore by the process of jigging. See jig.

Joao Neto de Campos. Found on the Paranaiba River, Catalao district, Goyaz, Brazil, 1947. The weight of the rough is reported to be 201 carats. Further details lacking.

 
Jalmeida Diamond jargon Jewel Box Jewelers' Security Alliance of the United States PDF Print E-mail
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Friday, 21 September 2007

Jalmeida diamond. A light-yellow stone weighing 109.50 carats in the rough. Discovered in the Bandeira River, Goyaz, Brazil, in 1942. Origi­nally acquired by Steinbert & Byr-kett, Rio de Janeiro jewelers. Report­edly cut to 45.40 carats. No addi­tional information.

jargon. A term once used for an in­ferior diamond having a yellowish color. May be confused with jargoon, a variety name for colorless zircon.

Jarra Gem. Trade name for synthetic rutile.

Java Gem. A trade name for synthet­ic rutile.

Jeffries, David. Prominent English jeweler and diamond expert of the 18th century. Author of "A Treatise on Diamonds and Pearls," published in 1750, in which he set forth rules for the evaluation of rough and fashioned diamonds and discussed their subsequent manufacture.

Jewel Box. A popular name given to a section of kimberlite in the old Roberts-Victor Mine, Republic of South africa, that was a particularly prolific producer of fine-quality dia­monds.

Jewelers' Security Alliance of the United States. A mutual, non-profit association, organized in 1883 for the protection of the jewelry industry. The Alliance offers many services and cooperates with all law en­forcement agencies; investigates crimes, prevents the commission of crimes by advocating burglar alarms and protective devices; supplies free detective services, provides members with warning signs; issues informa­tion on how to prevent various kinds of jewelry-related crimes. Headquar-


ters: 6 East 45th Street, New York,

New York 10017.

Jewelers' Vigilance Committee. A

non-profit association founded in 1912 to advance ethical practices in the jewelry trade. It is composed of representatives of every branch of the jewelry industry. The Commit­tee's purposes are: to be prepared to meet promptly any situation which imperils any broad interest in the trade; to protect the trade's prestige and endeavor to maintain public confidence in the jewelry industry, particularly the retailers; to fight any discrimination against the trade through government action; to help maintain fair competition within the industry; to develop and help main­tain trade standards on the highest possible levels; to assist in the pros­ecution of violators of the various laws, rulings, and regulations per­taining to advertising; to correct nomenclature and quality markings; to assist the government to combat smuggling and protect the industry from it; and to keep the trade in­formed of laws and regulations af­fecting its business. Headquarters: 919 Third Avenue, New York, New York 10022.

Jewelite. Trade name for man-made strontium titanate.

Jewelry Industry Council. This is the nationwide publicity and promo­tional organization of the entire in­dustry, with a membership consisting of jewelry retailers and suppliers. Its basic objective is to keep retail jewelry sales at the highest possible level. This is accomplished by the following activities: it prepares and releases for newspapers, magazines,


radio and television and other com­munications media a steady stream of publicity stories about the desira­bility of jewelry-store merchandise. It creates and furnishes sales-pro­motional material for retailers, in­cluding booklets for public distribu­tion, advertising and display ideas for newspapers, direct-mail service, radio commercials, window displays, Christmas portfolios, display cards for gift occasions, speech manu­scripts and fashion reports. Head­quarters: 608 Fifth Ave., New York City 10020.

 
Jagersfontein Rough Diamond Jahangir Diamond PDF Print E-mail
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Friday, 21 September 2007

Jagersfontein Rough diamond. A 215-carat diamond that was found in the Jagersfontein Mine, Republic of South africa, in 1881. There seems to be no record of its being cut. The ul­timate disposition of this stone is not known.

Jahangir Diamond. The inscriptions on this 83-carat diamond indicate that it was an heirloom of the em­perors of the Mogul Dynasty and was probably used to hold the ceremo­nial plumes on their turbans in place. The Persian engravings show that it first belonged to the Emperor Jahan­gir and then to his son, Jehan. In 1954, it was sold in London by its owner, the Maharajah of Burd-wan, to Stavros S. Niarchos, Greek shipbuilder and industrialist, for £13,000. In 1957, the Jahangir again changed ownership, this time being sold to an Indian businessman, C. Patel, for £14,000, in whose posses­sion it presumably rests today.

 
jaca Jacob Diamond Jager (yah"-ger) Jagersfontein Brilliant Diamond PDF Print E-mail
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Friday, 21 September 2007

jaca. A Brazilian term for spots in Diamonds.

Jacob diamond. Long identified with the Nizam of Hyderabad, the 100-carat Jacob was reported to be for sale in 1951, together with a large part of the Nizam's jewels. In 1956, it was held for sale by the Bank of India for $280,000. An American dealer at that time described it as "white, not blue" and not the most brilliant gem he had seen. The pres­ent owner of this diamond is not known.

Jacobs, Erasmus. A 15-year old farmer's boy who is credited with the discovery of the first diamond in South africa, in 1866. The stone that he found near the Orange River weighed 21.25 carats. See oreilly

DIAMOND.

Jager (yah"-ger). A term used to des­ignate a stone that displays a faint tint of blue. The name was adopted from the Jagersfontein Mine, since a relatively high percentage of its pro­duction consists of such stones. The blue tint associated with these stones is usually, but not always, the result of strong blue fluorescence. See fluorescence, blue diamond, jagersfontein

MINE.

Jagersfontein Brilliant Diamond. See

PAM DIAMOND.

Jagersfontein Mine (yah'-gers-fon-tane"). The first diamond pipe mine in South Africa, discovered in 1870 on the Jagersfontein farm near Fauresmith, Orange Free State. The


Jagersfontein Mine was closed May 28, 1971. Although the mine pro­duced a large proportion of cleavage fragments and heavily spotted goods, the output was characterized by a high proportion of fine colors, in­cluding stones that appear faintly blue in daylight; such stones usually, but not always, owe their color to strong fluorescence. The Excelsior, the Jubilee, and other large but un­named diamonds were found there. Annual production was usually be­tween 100,000 and 150,000 carats. See iager, fluorescence. Jagersfontein R
 
Isabella Diamond Isle of Wight diamond. Israel Export & Trust Corporation Ituiutaba Diamond PDF Print E-mail
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Friday, 21 September 2007

Isabella diamond. A 65/8-carat diamond reportedly owned by Queen Isabella of Spain. It was the pendant in a necklace given to Baby Doe Tabor of Colorado by her sec­ond husband, Senator Tabor, the "Bonanza King," in 1883. After Tabor lost his fortune, Baby Doe sold her jewels and the whereabouts of the Isabella is unknown today.

Isle of Wight diamond. A misnomer for rock crystal.

isometric system. See cubic system.

isotropic (ice'-oh-trope"-ik). See

SINGLE REFRACTION.

Israel. See cutting centers.


Israel Export & Trust Corporation.

An organization in the Ivory Coast that owns a license authorizing it to import and export Diamonds. See

IVORY COAST.

Ituiutaba Diamond. Found in 1940 in the Ituiutaba Mine, Minas Gerais, Brazil. 105 carats. Disposition un­known.

Ivory Coast (Cote d'lvoire). An au­tonomous republic that was formerly a French colony a part of French West africa. It is an important pro­ducer of alluvial diamonds. The min­ing companies operating in the Ivory Coast are Societe de Recherches et d''Exploitations Minieres en Cote d'lvoire (SAEAMCI) and Societe Diamandtifere de la Cote d'lvoire (SAREMCI). Diamond production in 1975 was reported to be 125,000 carats industrial and 84,000 carats gem quality. See French west africa.


 
Iranians iris diamond irradiated diamond PDF Print E-mail
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Friday, 21 September 2007

Iranians. A study of the Crown Jewels of Iran in 1966 by Dr. V. B. Meen and Dr. A. D. Tushingham revealed that there were 23 large Diamonds which they named the Ira­nians. There are 19 yellow stones of South African origin which were probably acquired in 1889 by Shah Nasir ud-Din during his trip to Europe. Four diamonds that may be of Indian origin include Iranian 19, 22, and 23, which are white stones, and Iranian 20, a peach-colored diamond. Iranian 23, weighing 38.18 carats, is thought by some experts to be the Hornby which was described by Edwin Streeter in 1882. The Ira­nian listed weights (ct.), shapes, and colors are:

1 152.16 rectangular old bril-

liant; silver cape

2 135.45 high (old) cushion, bril-

liant; cape

3 123.93 high (old) cushion, bril-

liant; silver cape

4 121.90 multifaceted octahed-

ron; cape

5 114.28 high (old) cushion bril-

liant; silver cape

6 86.61 rounded triangular bril-

liant; cape

7 86.28 irregular Mogul cut;

silver cape

8 78.96 high (old) cushion bril-

liant; cape


9 75.29 high (old) cushion bril­liant; cape

10 75.00 pendeloque brilliant;

silver cape

11 75.00 pendeloque brilliant;

silver cape

12 72.84 irregular pear-shape;

champagne

13 65.65 rectangular (old) bril-

liant; cape

14 60.00 cushion brilliant; yellow

15 57.85 round brilliant; silver

cape

16 57.15 cushion brilliant; silver

cape

17 56.19 cushion brilliant; silver

cape

18 55.67 cushion brilliant; cape

19 54.58 irregular oval Mogul

cut; colorless

20 54.35 high (old) cushion bril-

liant; peach

21 53.50 high (old) cushion bril-

liant; silver cape

22 51.90 elliptical Mogul cut;

colorless

23 38.18 multifaceted trapezoid

cut; colorless

iris diamond. A European term for a diamond that has been given a coat­ing to cause iridescence, giving the appearance of increased dispersion. Irish diamond. A misnomer for rock crystal from Ireland.

irradiated diamond. A diamond that has been subjected to bombardment by fast electrons, neutrons, deute-rons, etc. The purpose of irradiation is to make the color of the stone more attractive and desirable. See cyclotron-treated diamond, electron-bombarded DIAMOND, PILE-TREATED DIAMOND.

irregulars and shapes. A grading term used at the mines for diamond



 
internal characteristic internally flawless Iranian Royal Treasury PDF Print E-mail
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Friday, 21 September 2007

internal characteristic-A general term used to refer to any internal im­perfections or flaw. See flaw, imperfec­tion.

internally flawless. A clarity grade which describes a diamond without internal imperfections or flaws but with minor surface blemishes such as scratches, small naturals, etc., which under a strict interpretation of the F.T.C. rulings would preclude its being called flawless. Usually, but not always, such stones can be im­proved to a flawless grade through polishing and with a negligible loss of weight.

internal strain. A stress set up in a diamond or other gemstone as a re­sult of structural irregularities or dis­tortion, usually brought about by an inclusion in the stone. See anomalous double refraction, polariscope.

intrusive rock. See igneous rock. Iran. See Iranian royal treasury

Iranian Royal Treasury. The Royal Treasury of Iran contains a number of famous Diamonds and an untold number of large stones with no re­corded history. It is unique in that the


currency of the country is backed not by gold reserves but by a huge col­lection of diamonds, pearls and other Gemstones. Among the famous dia­monds that are known to be in the Treasury are the Nur-ul-Ain, the Darya-i-nur, and the Taj-e-mah. One diamond weighing 38.18 carats is be­lieved to be the Hornby.

 
Industrial Diamonds of South-West Industrial Distributors inferior cleavage PDF Print E-mail
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Friday, 21 September 2007

Industrial Diamonds of South-West africa (1945), Ltd. (Indosa). The company that works Saddle Hill and Saddle Hill North in the Luderitz dis­trict of South-West Africa. See

LUDERITZ.

Industrial Distributors (1946), Ltd.

The organization within the De Beers-diamond Corporation struc­ture that purchases industrial dia­monds for classification and mar­keting through Industrial Distributors (Sales), Ltd.

Industrial Distributors (Sales), Ltd. The organization that classifies and markets to the industrial-diamond trade the industrial diamonds it purchases from Industrial Dis­tributors (1946), Ltd. This company now confines itself to the marketing of crushing bort and drilling dia­monds. All other diamonds are mar­keted through the Diamond Trading Co.

inert. No detectable reaction, such as fluorescence, to stimulus when exposed to radiation from X-rays, ul­traviolet or cathode rays. See fluor­escence.

inferior cleavage. A grading term used at the mines for a diamond block, or cleavage, that is more or less spotted and of poor color.

inherent vice. If an insured diamond is said to have suffered damage, the insurance adjustor must determine whether damage has occurred and, if


so, whether it is attributable to some characteristic weakness in the stone. Such weakness is called inherent vice. If damage has occurred, it is fully recoverable from the insurance company only if inherent vice is not involved.

in situ. A mineral found in place in a primary rock (i.e., diamond in kim-berlite), rather than in a position to which it has been transported by such agencies as water, wind, glacial action or gravity, is said to have been found in situ.

 
Indosa indrajudha Industrial Diamond Association of America, Inc PDF Print E-mail
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Friday, 21 September 2007

Indosa. See industrial Diamonds of

SOUTH-WEST africa (1945), LTD.

indrajudha. A Sanskrit word for dia­mond, meaning "Indra's weapon." industrial diamond. As a general term, it refers to nongem-quality diamonds that are suitable only for industrial tools, abrasives, drills, etc. Gem-quality crystals, however, are also used for tools and particularly for dies, where lack of both internal strain and flaws is required. In this capacity, such a stone would also be called an industrial diamond. See

BALLAS, BORT, CARBONADO, HEAT CONDUCTION, TYPE II DIAMOND.

Industrial Diamond Association of America, Inc. An organization com­posed of diamond-tool manufactur­ers and others associated with the American industrial-diamond indus­try. It aids its member firms by en-

 
Indonesia Indore Pears PDF Print E-mail
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Friday, 21 September 2007

Indonesia, Republic of. A minor, sporadic producer of Diamonds. Sys­tematic alluvial mining was being conducted by the natives when the Dutch first arrived in the 17th cen­tury. At that time, the producing areas were situated in the vicinity of Pontianak, on the west coast of the island of Borneo, along the Kupuas, Sikajan, and Landak Rivers. The most important deposits at the present time are in the vicinity of Bandjer-masin and Martapura, on the south coast. Most of the diamonds recov­ered are small, but a significant proportion are of gem quality. An ex­ceptional number of colored diamonds have been found. diamond production in 1 975 was reported to be 3,000 carats industrial and 12,000 carats gem quality. Occasional re­ports of new finds suggest that the Kalimantan (Borneo) deposits, all of which are alluvial, are not exhausted.

See TRI-SAKTI DIAMOND, KALIMANTAN.

Indore Pears. These are two pear-shaped diamonds weighing approx­imately 50 carats each. Originally from Indore, north-central India, they were once the property of Nancy Anne Miller of Seattle, who, in the 1920's, became the Maharanee of Indore, with much attendant public­ity. After her subsequent divorce from the Maharajah, she continued to live in Indore but the diamonds were sold to Harry Winston, New York City gem dealer, and exhibited by him at the Court of Jewels at the New York World's Fair in 1939. They are believed to have been sold by Mr. Winston in the mid-1950's. The Indore Pears were repurchased by Harry Winston, New York, in 1976 and sold later in the same year


through the Geneva branch of Harry

Winston, Inc.

 
imperfection impregnated diamond dressing tool included crystal Independencia Diamond PDF Print E-mail
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Friday, 21 September 2007

imperfect. The diamond imperfec­tion grade at the low end of the flawless-to-imperfect (or perfect-to-imperfect) scale. An imperfect diamond contains imperfections that are visible face up to the unaided eye or that have a serious effect on the stone's durability. See clarity grade.

imperfection. A general term used to refer to any internal or external flaw or blemish on a fashioned diamond; e.g. a feather, carbon spot, fissure, knot, scratch, natural, etc. The terms flaw, characteristic and imperfection are usually used interchangeably. See

BLEMISH, FLAW, INTERNAL AND EXTERNAL CHARACTERISTIC.


imperfection grade. See clarity grade. Imperial Diamond. See victoria

DIAMOND.

impregnated diamond dressing tool.

A multiple-diamond dressing tool that contains several Diamonds not in a pattern throughout the matrix of the tool.

included crystal. A crystal of diamond or other mineral enclosed during the growth process of the main diamond crystal. It may be transparent in nature or dark appear­ing and usually assumes an angular outline. Sometimes called a "bubble" by jewelers due to its appearance.

inclusion. Any visible internal foreign object, or any crystal or grain of the same material as the host, or any break in a diamond or other gemstone can be called an inclusion. Breaks such as fractures and cleav­ages, however, are not always con­sidered inclusions. Independencia Diamond. Found in 1941 on the Tyuco River, Minas Gerais, Brazil, 106.82 carats. Present location not known.


index of refraction. See refractive in­dex.

 
illusion setting imitation immersion cell PDF Print E-mail
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Friday, 21 September 2007

illusion setting. Setting in which a stone, usually a small diamond, is set in a large polished or reflective plate fixed by claws in order to increase its apparent size. This setting appears as a continuation of the stone and was developed by the French jeweler Massin in the late 19th century for small stones.

imitation. In its broadest sense, any­thing that simulates a genuine, nat­ural gem. Gemologically, the term is applied only to glass, plastics and other amorphous materials, as distin­guished from synthetics and assem­bled stones.

immersion cell. Any cell used to immerse a diamond or other gem-stone in a liquid as a means of over­coming reflection and refraction from its surface, thus providing more ef­ficient observation of its interior. Immersion cells usually have glass bottoms, to facilitate their use with microscopes, polariscopes, etc.

the refractive index of a stone. Also, a rough guide to the refractive index by the immersion contrast method of using known stones and comparing with an unknown one. The more useful liquids are listed with refrac­tive indices: water (1.33), clove oil (1.54), bromoform (1.59), monobro-monaphthalene (1.66), and methy­lene iodide (1.74).

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