Decades ago, the value of a diamond was known only to those who could assess its rarity and beauty. Today, a number of international lists are available that suggest a price for every type of diamond. Of these, the Rapaport Diamond Report is the most widely used. These lists are used by diamond dealers and provide, at best, a pricing guideline.

Unfortunately, first-time buyers do not know how to use these list prices and may think they bought a bargain, but instead, bought a ‘dog’.

Depending on the rarity of the diamond and the expected state of future supply, actual transactions between dealers may be a few percent below the prevailing list price.

Important to know:

  • These price indications are based on the 4C’s and apply only to diamonds whose proportions, symmetry and polish each received an excellent grade. However, there are many other factors dealers use to discount the list price.

For instance:

* The larger top-quality stones (D-E/FL-VVS) trade at smaller discounts than the more commercial types.

* Fancy cuts stones such as princess, oval and pear shapes, etc., trade at about a 10% discount to similar quality round brilliants. Because more of the original rough diamond is lost in producing a round stone than when one with another shape is made.

* The presence of UltraViolet fluorescence may influence a diamond’s price.

Strong blue fluorescence may impart a milky white appearance to colourless stones which decreases their value, whereas blue fluorescence in a yellowish stone may mask the tint and makes the stone appear whiter, thus of higher value.

According to the Rapaport List, the presence of strong blue fluorescence in colourless diamonds could affect the price negatively – up to 25%!

CLICK HERE: To learn more about fluorescence.

  • The Rapaport Report gives price indications for diamonds up to 10 carats only. Larger diamonds are extremely scarce and their price may differ significantly between dealers and from stone to stone
  • The reputation of the laboratory that had graded the diamond also influences its value. GIA certified stones or one with corresponding certificates from two independent laboratories may attract a small premium.
  • To price natural Fancy coloured diamonds requires expert knowledge as the purity and intensity of the hue, amongst other factors, influence its value. Natural fancies with a vivid hue may demand prices that are close to or in excess of that of D-E colours.
  • Colour enhanced or synthetic fancy colour diamonds should not cost more than commercial qualities with a tint.
  • Branded diamonds (Hearts & Arrows, Tiffanies, Forevermark, etc.) normally carry a premium depending on its demand and availability.

SUMMARY: Two diamonds with the same shape, carat weight, colour and clarity may differ in price by more than 30%. Beware a slick salesman – there is a reason why his stone is offered at a ‘bargain.’

For peace of mind trust only an expert with a proven track record.