Visitors to the Royal Mint's website are being met with virtual queues as coin collectors attempt to snap up the first Sovereign coin to feature the portrait of King Charles.

The memorial coin, which pays tribute to the reign of Queen Elizabeth II, features the first official coinage portrait of the new monarch on the other side.

With new 50 pence pieces featuring King Charles III not expected to enter circulation until next month, this bullion coin is the first Sovereign to be struck and sold by the Royal Mint which features His Majesty.

Interest in the coin has been so great that those trying to access the Royal Mint's website are being met with virtual waiting rooms and queues of thousands of visitors.

What is a Sovereign coin?

A Sovereign, or regal coin, has been associated with the British monarch since 1489 when Henry VII demanded 'a new money of gold' to demonstrate his family's wealth and status. Each Tudor monarch after him continued to issue Sovereigns during their reign until the coin made way for a new one called the Unite.

But in 1817 the Sovereign coin was reborn and subsequently reissued by successive Kings and Queens - with Queen Elizabeth II changing the design of three Sovereigns issued during her reign to mark her Golden, Diamond and Platinum Jubilees.

To mark her death, the Royal Mint's memorial edition of the Sovereign features another change in the reverse design with the Royal Arms chosen to represent the life and legacy of Britain's longest-reigning monarch. While her son and heir is on the obverse side for the first time in the coin’s history making King Charles the eleventh king to feature on the ‘chief coin of the world’.

Prices for the new memorial Sovereign, which can be bought from the Royal Mint's website, range from £230 up to £5,595 however the top-price coin gold-proof coin sets in the collection costing £2,395 and £5,595 are no longer available according to the online shop.

A new 50p

The Royal Mint has also now started manufacturing the first circulating coins that will feature the new portrait of King Charles III.

Described as the 'biggest change to UK coinage since decimilisation, the newly struck 50 pence pieces are expected to begin appearing among people's change from next month.

The first coin will also be a memorial 50 pence in honour of the late Queen and the Royal Mint is expected to produce almost 10 million 50 pences in tribute to her reign.