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The Spark of Confidence

Glossary

Pavilion

Lower part, or ‘bottom half’, of a diamond below the girdle.

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Pavilion Angle

Angle measured between the girdle plane and the pavilion main facets.

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Pavilion Depth

Distance in millimeters or percentage from the girdle to the culet.

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Pavilion Depth Percentage

Pavilion depth expressed as a percentage of the diameter. Pavilion depth is an extremely important proportion to the brilliance of a diamond; diamonds with a pavilion that is too deep will have a nailhead, while diamonds with a pavilion that is too shallow or flat will have a fish eye.

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Pavilion Main Facets

Kite-shaped facets clustered from the culet and extending to the girdle.

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Pear Cut

Diamond cut or shaped into the outline of a tear-drop or a pear, with a rounded head tapering to a point.

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Phosphorescence

Phenomenon that causes some diamonds to continue “glowing in the dark,” after a light source is removed. Phosphorescence is much more common in synthetic diamonds than in natural diamonds.

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Pink Diamond

A coloured diamond with a natural pink body colour. Pink must be the predominant colour, but it may be modified by shades of purple, orange, and yellow. The colour in natural pink diamonds is created by irregular crystal structure. Some pink coloured diamonds with sufficient saturation fall into the valuable fancy pink colour category of diamonds.

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Pinpoints

Very tiny diamond crystal inclusions that are too small in size to distinguish their individual shapes. One pinpoint looks like a small “dot” under 10x magnification. Clusters of pinpoints create a cloud.

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Pit

Type of diamond blemish that appears as a tiny opening or indentation on the surface of a diamond. Large pits are called cavities. Pits affect the polish grade of a diamond.

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Pitted Facet

Diamond facet with numerous pits. Pitted facets affect the polish grade of a diamond.

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Plotting Diagram or “Plot”

Diagram of the approximate relative size, location, and type of internal inclusions and external blemishes of a diamond. A plotting diagram is often used for identifying a particular diamond.

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Point

Term for one hundredth of a carat. For example, a fifteen-point diamond weighs 0.15 carats. It could also be called a fifteen “pointer”.

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Polish Grade

Qualitative analysis of the overall surface condition of a diamond. The quality of polish is determined by the care put in by a polisher when finishing a diamond, and is important to the brilliance and scintillation given off by a diamond.

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Polish Lines

Lines left on the surface of the diamond which are visible under magnification, normally removed during the final diamond polishing process. Polish lines can affect the polish grade of the diamond.

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Polished Girdle

Describes the girdle of a diamond that has been fully polished smooth and clear around the entire perimeter. Step cut diamonds such as emerald cut and baguette cut diamonds usually have a polished girdle, and some brilliant cut diamonds may have polished girdles as well.

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Princess Cut

Diamond cut or shaped into a square or rectangle. Princess cuts combine features of both step cut and brilliant cut diamonds.

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Proportion Grade

Qualitative analysis of the overall proportions on a round brilliant cut diamond. Fancy shaped diamonds are not proportion graded; unlike round cut diamonds, there is no defined range of proportion standards for fancy shapes.

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Proportions

Relations between the dimensions and angles of a finished diamond. Examples of specific proportions are table size, depth percentage, and crown angle. Proportions are extremely important to the beauty, brilliance, and life in a diamond. Click here to learn more about proportions on a diamond grading report.

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latest news

Monday 12 June, 2017

GEM DIAMONDS FINDS TWO LARGE ROCKS AT FLAGSHIP MINE IN LESOTHO

Africa focused Gem Diamonds has discovered two diamonds bigger than 100 carats at its Letšeng mine in Lesotho, which should help the company boost revenue and investors confidence.

Tuesday 6 June, 2017

KIMBERLEY DIAMONDS CLOSES ITS LAST MINE

Controversial Australia-based miner Kimberley Diamonds has put its last remaining diamond mine into administration after it failed to secure fresh funding.

Monday 5 June, 2017

DE BEERS GOES TO COURT OVER SOUTH AFRICA EXPORT LEVY

De Beers Consolidated Mines (DBCM) is reportedly appealing to the Pretoria High Court in South Africa to set aside a decision by the South African Minister of Minerals Mosebenzi Zwane requiring DBCM to pay a levy on diamonds exported from South Africa to Botswana for the purpose of aggregation.

Thursday 18 May, 2017

DE BEERS TAPS INTO POLISHED DIAMONDS MARKET WITH FIRST-TIME AUCTION

Anglo American’s De Beers, the world’s largest rough diamond producer by value, has decided to begin selling its own polished diamonds in auctions for the first time in its history.

Wednesday 17 May, 2017

SOTHEBY'S SELLS THE APOLLO AND ARTEMIS DIAMONDS FOR £44.9 MILLION

Wednesday 10 May, 2017

US WOBBLE TAKES SHINE OFF PANDORA SALES

Pandora reported strong growth in the first quarter, but US store closures and sluggish mall traffic dented its performance stateside.

Sunday 7 May, 2017

IMPORTANT ADVICE ON HOW TO SELL YOUR DIAMONDS

If you are you considering selling your diamond, but feel as though you have no idea how or where to begin with the process?