Many of us have never heard of Chameleon Diamonds, let alone probably ever seen one or held it in our hands, its that rare. However, if you were to ask a collector, a trader or an expert of precious stones, they would tell you being rare, these can fetch a hefty price. But are they in league with clear or fancy colored diamond? Learn more about Chameleon to make an informed choice.
What is a Chameleon Diamond?
The chameleon diamond is named so due to a distinct trait of changing colour in hot conditions or when kept for a prolonged periods in a dark place.
What is the color of a Chameleon Diamond?
When not treated or exposed to anything , its colour is usually olive or a grey yellowish green. However, whenever its heated to 120-150 degrees, the olive tint of the diamond, within seconds, turns into a rich cinnamon or, in some cases, an orange yellow tint.
The Color Change is temporary
Although, the dramatic change of colour described above is visible to the naked eye, but is often short-lived. This is especially true, in case of a chameleon diamond when stored in the dark: however, within 10 minutes it reverts to its usual olive tint.
The Reverse is also Rare
In addition to the behavior exhibited above, even rarer class of chameleon diamonds do not change colour from a dark to a light one. Rather, a ‘reverse shift’ occurs, mainly from yellow to olive.
What causes the color change?
Well! nobody knows for sure. Even the experts at institutions like GIA, who have run countless tests over 39 chameleon diamonds discovered so far don;t have a specific answer or a concrete theory to explain how it happens. Some of them believe the change of colour is due a hydrogen impurity in the stone’s chemical composition; while others believe that it has luminescent and phosphorescent properties.
How were the Chameleon diamonds discovered?
By rather an accident, when in 1943 a Peter Kaplan first recorded a chameleon diamond. He noticed by mere chance that a diamond that was resting on a hot polishing wheel slowly begun to change its hue.
How to identify a Chameleon diamond?
Until 1943, chameleon diamonds were thought of as just regular green colored fancy diamonds. However, when the very first chameleon diamond was recorded at the Gemological Institute of America (GIA), a test was devised to identify these.
In order to test whether a diamond can change colour, its heated at temperatures above 140 degrees in laboratory environment (done often at GIA). If the hue of a diamond is permanently changed then its a chameleon diamond.
How much are these worth?
Same as all rare diamonds, the factors that determine its price are (4Cs) : size, as well as the tone and depth of colour. Still, these specimens being so rare and often being mistaken as just regular fancy colored diamond , adds to the their value , subjectively based in collector assessment. If any indication at all, the sale value of Chameleon Diamonds at auction may serve as the best indication of their value. For instance, in November 2011 a chameleon diamond ring (8.8 carats) was sold by Christie’s in Hong Kong for $590,000.