Glossary & Picture Library, learn

The Spark of Confidence

Glossary

De Beers Forevermark

De Beers Forevermark diamonds with the unique serial number and logo.

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Depth

Distance in millimeters or percentage from the table plane to the culet. Also known as ‘total depth’ or ‘total height’.

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Depth Percentage

Total depth expressed as a percentage of the diameter.

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Diameter

Diameter is a reference measurement against which most of the proportions on a diamond are calculated. On a round brilliant cut diamond, this is the length in milimeters of a straight line going through the center of a diamond. Click here to learn which standard diameter measurements correspond to specific well-proportioned carat weights. On a fancy shaped diamond, this is the average measurement in milimeters of the length and width.

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Diamond

Mineral composed almost exclusively of crystallised carbon. Carbon, when subjected to extremely high temperature and pressure, changes form and crystallises into diamond. Only approximately 20% of natural mined diamonds are of gem quality; the remaining 80% are industrial grade diamonds.

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Diamond Bourse

Organisation of diamond industry members. The main purpose of a diamond bourse is to provide an environment for the trading of diamonds within a set of ethical business practices. All diamond bourses have a legal, ethical framework to enact regulations for members and protect consumer confidence. Also referred to as a ‘Diamond Club’.

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Diamond cleaning

Because your diamond when worn naturally attracts grease or oil, they will need periodic cleaning.

Even when touching a diamond with your fingers natural oils from your skin will change the brilliance of your diamond, making your diamond lose its lustre or brilliance.

A simple way to keep your diamond jewellery looking beautiful is a weekly bath in a household cleaning solution. A simple window cleaner will work. But make sure you give it a thorough rinsing followed by a very light brushing using an old tooth brush to remove the oils and cleaning liquid.  

Pay special attention to the underside of the ring and bottom of the stone, as this is where most of the oils or hand creams accumulate.  

Make sure when using a brush not to apply to much pressure especially if the jewellery is old or fragile.  This is a good time to check the diamonds are tightly set and none are missing.

Never use Chlorine, bleaches or abrasives when cleaning diamonds set in jewellery. This will remove the rhodium plating on white gold and could leave scratches which will attract even more dirt.

If the ring has fine claws or filigree work an ultrasonic cleaner is necessary to remove deep encrusted dirt behind the diamonds. High frequency sound waves and jewellery detergent fluid will remove hard to get to dirt and grime. Make sure this is done by a professional to avoid damage or loss of stones.

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Diamond Dealers Club of South Africa

Diamond bourse, or organisation of diamond industry members. The main purpose of the DDCSA is to provide an environment for the trading of diamonds within a set of trading practices. The DDCSA has a legal, ethical framework to enact regulations for members and protect consumer confidence.

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Diamond Dust

Minute particles of diamond, usually used as a high-quality abrasive for diamond polishing or industrial grinding, sawing, and filing.

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Diamond Gauge

Tool used to manually measure the dimensions of a diamond.

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Directional Hardness

The bonds between carbon atoms that make up a diamond are stronger in some planes than others; this means that diamonds are marginally harder at some angles than at others. Diamonds thus have certain planes of weakness along which they can fracture, split or break. Directional hardness is related to the toughness and durability of diamonds.

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Dispersion

Visible play of colours created by the break-up of light in a diamond. When light enters a diamond, it refracts then reflects off of the pavilion facets and separates into a rainbow of colours as it shines out of the crown facets. Also known as fire.

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Durability

Overall resistance to wear and damage, considering both hardness and toughness. Diamonds are the hardest gemstone on earth, but are not the toughest - they have directional hardness.

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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.