NATURAL PINK DIAMONDS BUYING GUIDE
Numerous theories have been posited as to how the pink is formed in pink diamonds. The prevailing theory is that the pink is caused when the diamond is subjected to enormous pressure during its formation. A similar theory is being tested on pink diamonds that originated in the Argyle Mine in Kimberley, Western Australia. This theory posits that a seismic shock propelled colorless diamonds to the surface and altered their molecular structure, causing them to appear pink.
Properties determining value
The same four basic parameters that govern the grading of all gemstones are used to grade pink diamonds–the four Cs of connoisseurship: color, clarity, cut and carat weight. Color is considered the absolute most important criterion in grading a pink diamond and determining its value. However, size is an important consideration in a pink diamond's value. The larger a pink diamond, and the better its color, the more valuable it will be.The most famous pink diamond is the Pink Star diamond, a 59.60-carat fancy vivid pink type IIa diamond, which is the largest vivid pink diamond in the world and whose buyer at auction was unable to pay the promised sum and was subsequently forced to default.The Daria-i-Noor diamond and the Noor-ul-Ain diamond are the oldest known pink diamonds, and both belong to the Iranian crown jewels.Several other famous pink diamonds exist as well.
As with the color in all fancy color diamonds, the color in pink diamonds is assessed according to its hue, saturation and tone.
The hue refers to the primary and secondary colors, the saturation refers to the distribution of color, and the tone refers to the darkness of the color. Pink diamonds can occur in hues ranging from brown-pink to purple-pink, although pink can also be a modifying color in other diamond colors. Brown, orange and purple are the only occurring secondary hues in pink diamonds although a pink diamond can exhibit both brown and orange overtones at the same time, making it a "brownish orangey pink" diamonds.
The ideal pink diamonds are generally considered to be those which exhibit pure pink color although purple-pink diamonds are generally very highly regarded as well. Generally speaking, a vivid pink diamond will be more valuable than a larger lighter pink diamond, although it is not always the case according to the Diamond Investment & Intelligence Center.
Pink diamonds can occur in eight intensities, faint pink, very light pink, light pink, fancy light pink, fancy pink, fancy intense pink, fancy vivid pink, fancy deep/dark pink.
Just like in all fancy color diamonds, the more vivid intensity pink diamonds are far rarer than the less vivid, which is in part why they demand a higher price. The same cause in nature which is the course of the pink in pink diamonds can be more or less concentrated depending on the specimen. That is why it is so rare to find the most concentrated diamonds in each color. There is no perfect consensus as to what defines each color intensity grade, even though the GIA keeps a master catalog of each diamond color. Therefore, each color intensity also has a subscale of 1-10.
Pink diamonds fall under the category of Type IIa diamonds, meaning that they form under remarkably high pressure for longer time periods, and tend to have an irregular shape. They have no visible absorption, no nitrogen impurities that may cause a yellow or brown tint.
The Argyle Mine, the world's current main source for pink diamonds, has developed their own pink diamond color classification system separate from that of the GIA. Instead of intensity, the color is divided into a scale from 1-9, 9 being the lightest and 1 being the darkest. However, Argyle pink diamonds still receive GIA certificates.
All diamonds are examined under a loupe to determine their clarity. This 10x magnification determines whether or not the diamond exhibits inclusions either on its surface or inside. Like all diamonds, pink diamond clarity is measured on a scale from Flawless to Included. Only 7% of pink diamonds are either Flawless or Internally Flawless (IF), and majority are Slightly Included (SI) Like most of the colors of fancy color diamonds, the clarity has little effect on a pink diamond's value. Since pink diamonds are formed by a deformation on their lattice structure, their probably of a low clarity grade is higher, making high clarity pink diamonds extremely rare (<7%).
According to the GIA, more than 80% of pink diamonds display fluorescence. It is so rare for a pink diamond not to have fluorescence that in the case of pink diamonds, one that does not display fluorescence will actually be priced lower than one that does, out of suspicion that the diamond may be fake.