Anticipation is high that a world record price will be achieved next month for a fancy, intense pink, 24.78 carat stone, purchased from jeweler Harry Winston about 60 years ago. The rare pink diamond comes to market with an estimate of 27,000,000 to 38,000,000 million CHF (US $27,855,000 - 39,203,460) at a Sotheby's sale in Geneva on November 16.

The low estimate for this perfect pink piece is about $3 million higher than the top price ever paid for a gem.

Prices for diamonds and other colored-stone jewelry have increased 20 percent from just a year ago, according to Reuters.

On Oct. 20, the Bulgari Blue Diamond was the top lot in Christie's historic $50-million jewels sale. The ring, designed in the 1970s, fetched $15.7 million, or $1.4 million per carat, the highest price paid per carat for a blue diamond. The piece tripled in value for the European collector who consigned it.

The Sept. 15 Fine Jewelry and Timepieces sale at Chicago-based Leslie Hindman Auctioneers saw many estimates soundly surpassed. Among the highlights, an octagonal step cut ring set in platinum with baguettes garnered $158,600 against an estimate of $30,000 to $50,000.

"As buyers around the world seek reliable material investments, we are capitalizing on the fine jewelry market to achieve extraordinary prices for our consignors,” remarked auctioneer Leslie Hindman in a statement.

Newer and antique pieces have both proved popular. A magnificent late art deco Asscher-cut diamond ring, weighing 6.82 carats, D colour and potentially flawless, sold for £322,000, which was over double its original lower estimate of £150,000, at a Bonhams sale on Sept. 22.

In the past year, jewels owned by philanthropist Lenore Annenberg, actress Ellen Barkin, and other well known names have exceeded estimates. A 6.43-carat pink diamond set in a Van Cleef & Arpels ring, once owned by Princess Mary, daughter of Britain’s King George V, fetched just above its high estimate, HK$60 million ($7.7 million), in a Sotheby's Hong Kong jewelry sale in early Oct.

Christie's will offer a 14.23-carat fancy intense pink VVS2 rectangular cut diamond ring, estimated at $14-$19 million, in Hong Kong on Nov. 29. Last Dec., the firm sold a 5-carat, vivid pink diamond ring for $10.8 million, a record-shattering $2.2 million per carat.

The world record auction price for any jewel was set in December 2008 when the fancy grey-blue Wittelsbach Diamond brought $24.3 million at Christie's London. Billionaire jeweler Laurence Graff bought this legendary diamond which was once owned by the Infanta Margarita Téresa of Spain and Bavaria's ruling House of Wittelsbach.

The American Museum of Natural History in New York City will unveil the renamed (and recut) Wittelsbach-Graff Diamond on Thursday, October 28, in the museum's Harry Frank Guggenheim Hall of Minerals. Graff, who controversially repolished and shaved off a few carats to make a flawless 31.06-carat diamond, is loaning the gem to the museum through January 2, 2011. It was previously on view alongside the comparable Hope Diamond at the Smithsonian's National Museum of Natural History.