Obverse. Photo © Royal Mint
  • 50 Pence 2022, Sp# H108, United Kingdom (Great Britain), Elizabeth II, Innovation in Science, Alan Turing
  • 50 Pence 2022, Sp# H108, United Kingdom (Great Britain), Elizabeth II, Innovation in Science, Alan Turing
  • 50 Pence 2022, Sp# H108, United Kingdom (Great Britain), Elizabeth II, Innovation in Science, Alan Turing, Box with a certificate of authenticity
  • 50 Pence 2022, Sp# H108, United Kingdom (Great Britain), Elizabeth II, Innovation in Science, Alan Turing, Hidden codes
Description

A piedfort is an unusually thick coin, often exactly twice the normal weight and thickness of other coins of the same diameter and pattern. Piedforts are not normally circulated, and are only struck for presentation purposes by mint officials (such as patterns), or for collectors, dignitaries, and other VIPs.

Alan Mathison Turing (1912–1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher, and theoretical biologist. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. He is widely considered to be the father of theoretical computer science and artificial intelligence.

Estimated to have saved millions of lives by shortening the war, his codebreaking logic applied during the Second World War along with fellow codebreakers serves as an act of intellectual heroism. In recent years, Turing has become a figurehead for gay rights following his posthumous pardon from Her Majesty The Queen in 2013, which has since led to further pardons to gay men and created what’s become known as ‘Turing’s Law’.

Recently honoured by the Bank of England by the inclusion of his portrait on a new £50 note, this is the first time the Royal Mint has commemorated Alan Turing on a UK coin.

Obverse

The fifth crowned portrait of HM Queen Elizabeth II facing right, wearing the George IV State Diadem and drop earrings.

The George IV State Diadem, officially the Diamond Diadem, is a type of crown that was made in 1820 for King George IV. The diadem is worn by queens and queens consort in procession to coronations and State Openings of Parliament. The piece of jewellery has been featured in paintings and on stamps and currency. It can be seen in the Queen's Gallery at Buckingham Palace.

ELIZABETH II DEI GRATIA REGINA FIDEI DEFENSATRIX means Elizabeth II, by the grace of God, Queen and Defender of the Faith.

Engraver: Jody Clark

·ELIZABETH II·D·G·REG·F·D·50 PENCE·2022
J.C

Reverse

Depicts it will show a wheel from Turing's anti-Enigma bombe and the inscription ALAN TURING set against a background of letters. The design incorporates elements of codebreaking as a fitting tribute to Alan Turing, also there are three hidden codes:

1. The what3words geocode system directs to Cambridge University, where Alan Turing studied mathematics when the code 'GEARS GRIN THAN' is entered.
2. The quote, "ONLY A FORETASTE OF WHAT'S TO COME", pertains to his Bombe code-breaking machine.
3. The designer's initials for the object in question are CD and MD.

The bombe was an electro-mechanical device used by British cryptologists to help decipher German Enigma-machine-encrypted secret messages during World War II. The initial design of the British bombe was produced in 1939 at the UK Government Code and Cypher School (GC&CS) at Bletchley Park by Alan Turing.

Engraver: Matt Dent and Christian Davies

ALAN TURING

Edge

50 Pence

5th portrait, Silver Proof Piedfort Coin
Sp# H108
Characteristics
Type Commemorative Issue (Non-circulating)
Material Silver
Fineness 0.925
Weight 16 g
Diameter 27.3 mm
Thickness -
Shape polygon
Sides 7
Alignment Medal
Mint
Royal Mint

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