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The Spark of Confidence

Glossary

Calf’s Head Diamond

Diamond cut or shaped to look like a triangle with all three corners cut off, similar in outline to the head of a calf.

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Canary Diamond

Term used to describe an intensely or vividly bright-yellow fancy colour diamond.

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Cape Series Diamonds

A broad scale of diamond colour grades that ranges from a near colourless, almost undetectable pale yellow to increasingly tinted yellow. Once it has enough yellow saturation to qualify as a fancy colour, it is no longer called a Cape Series diamond.

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Carat

The standard unit of measuring the weight of a diamond. The origin of the word traces back to ancient times when diamonds were weighed on balances against carob beans, which held a consistent weight. One carob bean, or carat, weighs 1/5 of a gram.

Carob Bean

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Carbon

Diamonds are made of pure carbon that has been subjected to and crystallised under enormous heat and pressure. Without the pressure, graphite is formed instead of diamond. Other forms of carbon can be found in substances like coal, but these are impure forms of carbon.

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Carbon Spots

Small black graphite inclusions in a diamond. Diamonds are made of pure carbon that has been subjected to and crystallised under enormous heat and pressure. At times, not all of the carbon crystalises, and small black spots may remain.

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Cavity

Type of diamond inclusion that appears as an opening or large indentation on the surface of a diamond. A tiny version of a cavity is a called a pit. Cavities affect both the clarity grade and the polish grade of a diamond.

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Certificate

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

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Chameleon-Type Diamond

A very rare type of diamond that changes colour when exposed to different light and heat conditions.

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Champagne Diamond

Refers to a coloured diamond that is light-brown or light brownish-yellow in colour.

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Chip

Type of inclusion that appears as a slight break out of the edge of a diamond, larger than a nick. Chips are caused when a diamond receives a sharp knock or blow; they affect both the polish and clarity grade of a diamond.

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CIBJO

The World Jewellery Confederation, an international confederation of national jewellery trade organizations. CIBJO's purpose is to encourage harmonisation, promote international cooperation in the jewellery industry, and to consider issues that concern the trade worldwide. Foremost among these is to protect consumer confidence in the industry.

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Clarity

Term used to describe the relative presence or absence of inclusions in a diamond. Most diamonds, when formed, contain imperfections of one kind or another. Clarity, sometimes called purity, is one of the four c’s of diamond grading that determines the overall diamond quality and value.

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Clarity Enhancement

Any artificial treatment or process meant to improve the appearance of a diamond’s clarity. Laser drilling and fracture filling are examples of diamond clarity enhancement. Click here to learn more about diamond clarity enhancements.

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Cleavage

Type of inclusion that appears as a fairly smooth split or crack in a diamond, found along a plane of weakness. Cleavage is due to the directional hardness of diamonds.

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Closed Table

Trade term for a diamond that has a relatively small table in relation to the size of the diamond. A small table reduces the amount of brilliance, but may increase the amount of fire.

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Cloud

Cluster of pinpoint inclusions creating a hazy or milky area in a diamond. A diamond cloud can range from extremely sparse and faint, to dense and heavy. Clouds may also be small and localised, or spread throughout an entire diamond and affect the transparency.

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Coated Diamond or Coating

Deceptive practice where a diamond is partially or wholly ‘painted’ with a colouring agent, either to hide unattractive colour, or to enhance desirable colour. To learn more about coated diamonds and diamond treatments, click here.

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Cognac

Refers to a coloured diamond that is dark brown in colour.

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Cold Laser Inscription

The use of a very fine, precise laser beam to write a grading report number or customised personal message on the girdle of a diamond, generally for identification purposes. Cold laser inscription is 100% safe for diamonds, compared to hot laser inscription. The laser inscription is invisible to the naked eye and can only be seen with a magnifying loupe. Click here to learn more about diamond laser inscription.

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Colour

Term used to describe the relative presence or absence of body colour in a diamond. Diamonds are either cape series diamonds or coloured diamonds.

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Coloured Diamond

Any diamond with a noticeable body colour other than white. Colour in diamonds is caused by either various impurities trapped in the diamond crystal as it was forming in the earth, or by irregularities in the crystal structure itself. Some coloured diamonds fall into the valuable fancy colour category of diamonds.

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Conflict Diamonds

Diamonds that originate from areas controlled by rebel forces that are opposed to the governments in power, and are used to finance wars against these governments. Along with the other resources like oil and timber The Kimberley Process has been put in place to combat trade these diamonds, also known as'blood diamonds'. Click here to learn more about conflict diamonds and the Kimberley Process.

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Crown

Upper part, or ‘top half’ of the diamond, above the girdle.

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Crown Angle

Angle measured between the girdle plane and the bezel facets. Crown angle together with table size determine how much fire (dispersion) and brilliance a diamond shows.

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Crown Height

Distance in millimeters from the table to the girdle.

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Crown Height Percentage

Crown Height expressed as a percentage of the diameter.

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Crystal

Type of inclusion where a mineral deposit, or sometimes another diamond, is trapped inside the diamond. Crystals often look like bubbles of various shapes and sizes.

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Cubic Zirconia

Colourless, transparent, man-made material that is often used to imitate diamond - a diamond simulant.  The chemical name is zirconinum dioxide (ZrO2).

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Culet

Tiny point on the bottom of a brilliant cut diamond, or the bottom edge of a step cut diamond.  A culet can be prone to damage, thus diamonds are usually set in jewellery in such a way that the culet is protected.

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Cushion Cut

Diamond cut or shaped into a squarish or rectangular outline, with rounded corners.  A brilliant cut cushion is one of the diamond shapes that can display hearts & arrows.

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Cut

Can refer to any or all of the following: proportions, polish, symmetry, and/or shape and style of cutting (brilliant cut or step cut). The overall cut grade is one of the four c’s of diamond grading that determines the overall diamond quality and value.

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Cut Grade

Qualitative description of the overall make of the diamond, taking into consideration the proportions, polish, and symmetry. Cut is one of the four c’s of diamond grading that determines the overall diamond quality and value.

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Cut-for-Weight

A diamond that is fashioned so as to minimise the amount of rough diamond crystal cut away. Carat weight may be gained, but brilliance, fire, and beauty are lost. The resulting proportions can make some diamonds look ‘bulgy,’ 'lumpy', ‘deep,’ or ‘undersize,’ while others may be flat or have symmetry deviations.

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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.