This week, Christie's offered a spectacular and extremely rare coloured diamond. This was the Vivid Yellow, a rare, highly saturated fancy vivid yellow diamond of 32.77 carats, as the star lot of its October 18 sale of Magnificent Jewels.

The golden yellow hue of this large pear-shaped stone is so intense and so deep that the Gemological Institute of America (GIA) ranks it amongst the rarest of gemstones in its class. The stone is expected to achieve in excess of $6m.

"The Vivid Yellow literally blazes with colour, unlike any yellow diamond I've ever seen," enthused Rahul Kadakia, Head of Jewellery for Christie's Americas, ahead of the sale.

"In the world of diamonds, a naturally coloured stone of this incredible colour and size represents a freak occurrence -- an extremely rare geological phenomenon. The appearance of this extraordinary gemstone on the market truly represents a once in a lifetime opportunity for top jewelry collectors."

Simply dazzling... the fancy vivid yellow diamond

Yellow diamonds gain their colour from nitrogen replacing carbon atoms in the diamond's structure. Where there is less nitrogen present, the resulting stone may be light or "faint" in colour.

The results are now in for the sale with the whole Magnificent Jewels auction on October 18 achieving $46.6m.

As expected, the Vivid Yellow was the top lot, selling for $6.6m to an anonymous bidder.

Rahul Kadakia, commented: "Despite recent volatility in the financial markets, the jewelry world continues to hold strong with active participation from top private collectors and members of the trade for superb gems and jewels.

"At $201,000 per ct, the 32.77 ct VIVID yellow diamond achieved a sensational price, mirroring the $203,000 per ct realized by The Golden Drop of 18.49 cts at Christie's London back in 1990. Having set the stage for our fall season, we look forward to our November 16 jewelry auction in Geneva."