An 8.41-carat pear-shaped fancy vivid purple-pink diamond is going to be auctioned by Sotheby's Hong Kong in October 2014. Experts expect it to sell for more than $15 Million Dollars.

Even if the rare diamond reaches its low-bid estimate of $1.5m per carat, it would put it among the top three pink stones ever sold at auction on a per-carat basis.

However, Sotheby's expects its internally flawless fancy diamond to fetch between $12.8m and $15.4m at auction on October 7.

This color is one of the most beautiful and concentrated shades of pink in diamonds that I have seen and, combined with the exceptional clarity, it is not surprising that it would command the highest per-carat pre-sale estimate for any pink diamond to date,” said Quek Chin Yeow, deputy chairman, Asia, and chairman international Jewellery, Asia.

Pink diamonds have been coveted by rulers and prized by connoisseurs since they were first discovered in the mines of India centuries ago. Strongly coloured diamonds belong among the most valuable diamonds in the world.

For instance, an orange diamond, the largest known to exist, has been sold for $36 million at Christie's International in Geneva, Switzerland in November 2013. The pear-shaped 14.82-carat diamond was auctioned at a record price, worth $2.4 million per carat. Nevertheless, the world-record price for the diamond is held by the flawless 59.60-carat Pink Star, which had been renamed "The Pink Dream", in an auction by Sotheby's the same month. The curiosity is that Sotheby's has had to re-acquire the Pink Star diamond, which originally sold for a record breaking $83 million, as it turned out that the buyer could not afford it.

New 8.41-carat pear-shaped diamond will tour Singapore, Taipei, New York, London, Geneva and Hong Kong prior to the auction.