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The Spark of Confidence

Glossary

Gem Quality

Diamonds of a beauty and calibre suitable to be used in jewellery. Only approximately 20% of mined diamonds are of gem quality  - 80% are in fact industrial grade diamonds.

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Gemmology

The science, art, and profession of identifying and evaluating of all gemstones, including diamonds.

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Girdle

The outermost edge or rim of a diamond that outlines its shape. It is the circumference or perimeter that appears to divide the crown from the pavilion. A girdle may be faceted, polished, or bruted. The purpose of the girdle is to protect the diamond from damage such as chips.

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Girdle Thickness

The height of the girdle, expressed both in millimetres and as a percentage of the total depth.

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Grading Report

A complete, accurate report describing the specific characteristics of a diamond, issued by a recognised and independent diamond grading laboratory. A diamond grading report lists all the characteristics of a diamond that allows you to determine its current appraisal and fair market value. Also called a Diamond Certificate. A diamond grading report is not an appraisal and does not contain a monetary value. Click here for a guide to the information that a diamond grading report must have.

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Grainer

Term used to describe a diamond weighing approximately 0.25 of a carat. In ancient times, 1.00 carat was equal to about four grains of rice. A “four grainer” would thus be referring to a diamond weighing approximately 1.00 carat (4 x 0.25=1.00).

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Graining

Faint wavy, hazy, oily, or distorted transparent and sometimes shadowlike lines, either inside the diamond or on the surface of a diamond. Graining is caused by irregular growth and crystallization that takes place when the diamond is formed. Also known as “growth lines.”

  

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Green Diamond

A diamond with a natural green body colour. Green must be the predominant colour, but it may be modified by shades of yellow or blue. The colour in natural green diamonds is created by exposure to natural irradiation in the earth that produces structural defects; natural green diamonds are extremely rare. Some green coloured diamonds with sufficient saturation fall into the valuable fancy green colour category of diamonds.

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latest news

Tuesday 25 April, 2017

CHRISTIE’S TO OFFER 92CT. PENDANT

A 92.15 carat diamond pendant worth up to $20 million will lead Christie’s Magnificent Jewels auction in Geneva next month.

Thursday 20 April, 2017

GRAFF UNVEILS 105-CARAT D-FLAWLESS DIAMOND

Graff Diamonds has unveiled the 105.07 carat D flawless pear shaped diamond, it has named the Graff Vendôme after its new retail outlet at Place Vendôme in Paris.

Monday 10 April, 2017

LETSENG MINE YIELDS 114CT. DIAMOND

Gem Diamonds has found a 114-carat rough diamond at its Letšeng mine in Lesotho, the miner reported Friday.

Tuesday 4 April, 2017

SOTHEBY'S SELLS 59.6 CARAT PINK FOR $94.2 MILLION AUD

Steinmetz Diamonds owned by Israeli billionaire Benny Steinmetz, spent two years cutting and polishing the Rough diamond. Which was mined by De Beers in Botswana, Southern Africa.

Thursday 30 March, 2017

DE BEERS, LUK FOOK TO CO-BRAND GRADING REPORTS

Tuesday 21 March, 2017

59.6 CARAT VIVID PINK DIAMOND

Sotheby's plans to auction the famous "Pink Star" diamond an internally flawless, fancy vivid pink stone at its sale in Hong Kong on April 4.

Wednesday 8 March, 2017

GIA FINDS SIGNIFICANT UNDISCLOSED SYNTHETICS

The Gemological Institute of America (GIA) recently uncovered an unusually large number of undisclosed synthetic diamonds mixed in with natural melee diamonds, the lab confirmed with Rapaport News on Monday.