"The greatest gold rarity of the British Empire” realized £480,000 ($753,211 U.S.), including 20 percent buyer’s fee, in a May 19 auction.

The accolade was used by St. James’s Auctions in describing its offering of a 1920-S gold sovereign coins struck at the Sydney Mint, then a branch of London’s Royal Mint.

One of four examples known, the piece was sold in the firm’s May 19 auction of the Park House Collection of gold sovereigns.

Though the 1920-S sovereign is a rarity with significant stature, the sale marked the third example in four years to be offered at auction. 

RELATED: read Coin World's earlier coverage of the Park House Collection sale

According to the auction house, the example it sold is the finest known of all extant pieces. The firm calls it a “proof sovereign” and “special strike,” and distinguishes it from other extant examples.

The auction house describes the coin just sold as “obviously specially struck with an unusual degree of sharpness on King George’s portrait,” with “the horse and dragon ... both boldly rendered” on the reverse.

The mintage for 1920 sovereigns is recorded as 360,000 pieces, but researchers believe the count includes 1919-dated pieces.

In 2012 another example of the 1920-S sovereign was sold as part of the Bentley Collection. Steve Hill of A.H. Baldwin & Sons Ltd., which conducted the sale, suggested that the 1920-S coins were made for some “special event.”

One of the four known examples is in a museum and the other two are now in private collections. 

The Bentley Collection piece (described as “practically as struck”) realized a hammer price of £780,000 ($1,261,520 U.S.), and the George Collection example (described as “virtually as struck”) sold for £542,500 ($904,472 U.S.) in a March 2014 auction by St. James’s.

The example sold in 2015 is “essentially” Uncirculated and was estimated to realize £400,000 to £500,000 (about $617,244 to $771,555 in U.S. funds).

1953 coronation coin

The other main star of the Park House Collection was the unique in private hands Proof 1953 gold sovereign marking the coronation of Queen Elizabeth II.

It sold for £360,000 ($564,908 U.S.), including the 20 percent buyer’s fee.

Though the Royal Mint did not issue Proof sovereigns for sale until 12 years after World War II, a small number of gold Proof sets were created for the coronation of Queen Elizabeth II. These sets were for institutional collections.

This example is only the second example ever to enter the market. Another example, once owned by Emory May Norweb (and last auctioned in 1985), was stolen and has since disappeared from the marketplace.

The example in the May 19 sale is in private hands only because the National Museum of Wales was given permission to sell it, since another example was in the nearby collection of the Royal Mint. 

The 1953 Proof gold sovereign was estimated at £250,000 to £300,000 (about $385,815 to $462,993 U.S.).

To learn more about the sale, visit the firm’s website.

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