Portcullis on British Coins

Portcullis on Reverse of a 1967 Brass Threepence

Portcullis on Reverse of 2006 Silver Proof Penny

The Portcullis on British Coins

Portcullis Design
The design on the reverse of the decimal penny is a "Royally crowned portcullis". This was originally a badge of Henry VII, the first of the Tudor monarchs. It was first used on coins as a mintmark on the first (gold) coinage of Henry VIII, but not on those of his son Edward VI. Under Elizabeth I, it was not only used as a mintmark, but also as the reverse design on silver "Testerns", which were trade coinage issued from 1600 to 1601, for use in trade with the "East Indies".
It was also used as a mintmark on coins of Charles I, for the last time until the time of Elizabeth II.

Elizabeth II
The portcullis design was re-introduced for the reign of Elizabeth II on the brass threepence. The thrift plant which appeared from 1937 to 1952 was replaced. After 1967 when the last brass threepence was produced, except for the proofs issued in 1970, the portcullis symbol transferred to the new decimal penny. this seems quite appropriate as the value of the new penny was equal to 2.4 old pennies, and was the closest in value to the old 3 pence coin.

Other Users of the Portcullis Symbol
According to the decimal coin sample wallets issued by the Royal Mint prior to decimalisation, the portcullis is also associated with the Palace of Westminster, i.e. Parliament.
It is also used as a symbol by H.M. Customs & Excise.

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