A numismatic collection which has been amassed over 40 years will be among the highlights at Heritage's 2010 October Stamford COINFEST Signature US Coin Auction, next week (October 28-31).

The Diotte Collection is being presented with much fanfare. Specifically, Mr Diotte's second collection will appear in the sale which showcases a favoured focus on early US coin types.

Starring among the collection's PCGS and NGC coins is the 1797 half dollar O-102 - "the prize of his collection," according to Heritage (and the third time that the auction house has sold this example).

The Draped Bust Small Eagle half dollar dates to 1796-97 and is, say Heritage's lot notes, "one of the most significant, if not the most significant, coins desired by advanced type collectors."

While neither the lowest-mintage nor the rarest type coin - those distinctions belong to the one-year design type 1796 No Stars and 1808 quarter eagles - half dollars from 1796-97 are the costliest out of all these examples on a grade-for-grade basis.

And, even though the coin comes with an NCS disclaimer referring to 'several shallow to medium-depth scratches on the coin's lower reverse which has since been toned over,' this is unlikely to impede its value. Even in the Fair 2 level of preservation, these specimens command five-figure prices.

The 1797 half dollar O-102: the prize of the Diotte Collection

Why is the half dollar O-102 so desired by numismatists? Well firstly it exhibits a relatively strong definition of the coin's design elements especially on its obverse. Liberty's lower and middle hair details are sharp, as are her facial details and the date (as pictured above).

Secondly, this coin is the rarest of the four 1796-1797 die marriages. In the most recent "Pre-Turban Bust Half Dollar Census" (published in the John Reich Journal, December 2009), expert Stephen Herrman gives the half dollar O-102 a "low R.6" rarity rating.

In other words, there are around 13-30 known examples of this very rare coin in the world. Due to the resulting supply and demand, there is a readily available market even for impaired half dollar O-102 specimens.

For these reasons, bids for the coin currently stand at $11,000 in Heritage's sale. Online bidding is available with the window set to close on October 27.

This coin and others from the collection are sure to continue Mr Diotte's successes as a coin investor. His first collection was reportedly sold in the 1970s to help finance the construction of a house.

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