As part of their sale of the Bentley Collection of British Gold Sovereigns, London based A. H. Baldwin & Sons Ltd. (Baldwin's) will auction one of the rarest Australian coins to have ever been offered for sale. 

To be offered in three parts, part two of the sale to be sold on the 27^th of September will feature an extremely rare 1920 Sydney Mint gold sovereign.  Also to be offered during part two of the sale will be the entire colonial branch mint series which includes coins from the three Mints of Australia: Sydney, Melbourne and Perth

Regarding the 1920 Sydney Mint sovereign Baldwin’s state that:

 “the greatest rarity in the Colonial Gold Sovereign Series, most specimens are housed in institutions and this represents an extremely rare opportunity to acquire a piece of numismatic history of the utmost importance.”

The Bentley Collection was started in the late seventies and began with a casual exploration into the possibility of owning some gold as a safe haven investment in the form of coin.  This quickly became a passionate quest to formulate one of the greatest collections assembled of the British Gold Sovereign.

Due to its rarity, the 1920 Sydney Mint gold sovereign was not added to the collection until 2006.  The final date-piece required for the currency part of the collection, the 1920 S coin was sourced from Australia and is considered to be the crown jewel of the Bentley Collection as well as arguably the most valuable currency coin in the entire Australian series.

In 2006 Australian auctioneers KJC Coins sold a 1920 Sydney Mint gold sovereign for a then record AUD$582,500.  This coin set a new world record for the highest price for any Australian coin or banknote ever sold at public auction as well as a world record price for any gold sovereign ever sold at a public auction. In 2009 the record was raised when Monetarium Pty Ltd sold a specimen from the Quartermaster collection for AUD$844,000.

Part one of the three part sale will take place on the 8^th of May and will consist of London Royal Mint issues both currency and patterns and proofs and one third of the Victorian die number series by quantity. 

The full catalogue can be viewed here:

http://www.baldwin.co.uk/auction-73/