Even though the world is reeling under a severe credit crunch, various auctions selling rare items are still making a lot of profits. And hoping to make some profits for themselves, Petra, a Jersey-based mining company, has chosen Sotheby’s to auction a rare blue diamond for them. The 7-carat jewel was cut from a 26.6-carat rough stone and is expected to fetch around $8.5 million! Sotheby’s will include the stone as the main attraction in its “Magnificent Jewels” auction in Geneva on May 12. But before it is auctioned off, the stone will be exhibited in major cities across the world including Hong Kong, Paris, New York and London. Since the prices of rough diamonds have seen a fall in the past few years, Petra had to opt for the auction.