Rare 25p Coin To Be Sold In RWB Auctions September Coin Sale

A rare experimental coin is to be offered in RWB Auctions 25 September coin sale.

Though it looks like an ordinary 20p at first glance, the experts in our Coin Department have identified this unusual coin as a 25p trial piece made by The Royal Mint.

One of only a handful of examples known to have been struck in nickel-brass, this is a true modern rarity sure to interest decimal collectors.

What Are Trial Pieces?

Trial pieces are sample coins produced before a new design or denomination is introduced. Mints make trial pieces to experiment with new materials and to test how new features perform when they are used in vending machines or cash-counting machines. Trial pieces may also be created to demonstrate a new royal portrait or a fresh reverse design to important decision-makers before it is formally approved.

Several variants can be produced before a trial goes into production, so these coins give us an interesting insight into how coin development works.

Only a small number of trial coins will be produced and an even smaller number make their way into private hands. Their rarity attracts attention from serious collectors and can lead to high hammer prices when these coins are sold at auction.

Obverse of the 1981 25p: at first glance, this seven-sided 25p trial coin could be mistaken for a standard 20p.

No Ordinary 20p

This trial piece has the same seven sided shape as the 20p which is properly known as an 'equilateral curve heptagon'. They also have the distinctive raised edge design that can be seen on 20p coins in our change today.

Unlike 20p coins, 25p trial pieces do not feature a portrait of the reigning monarch.

Instead, they show the Royal Mint's old crowned shield logo on one side with '1981' below and the words 'EXPERIMENTAL COIN' above. The other side reads 'ROYAL MINT TRIAL' with tiny national flower emblems below and a depiction of the Sovereign's Orb, part of the British crown jewels.

Reverse of the 1981 25p: tiny national flower emblems at the bottom of this trial coin include a rose, daffodils, shamrocks and thistles.

Mysterious Origins

Though this trial piece is dated 1981, its origins are unclear.

Some suggest that these coins were produced in the early 1980s when inflation had reduced the purchasing power of 10p and 5p coins. This created a need for a coin that filled the gap between these and the 50p which had been introduced in 1969, shortly before the UK formally decimalised its currency. Subscribers to this theory suggest that 25p trial pieces were a precursor to the 20p which was introduced in 1982.

However, others claim that despite the 1981 date, these coins were struck between 1994 and 1996 as the UK considered replacing the Pound with the Euro.

Nickel Brass Trial Coin

It has been estimated that there are less than 50 examples of the 1981 25p trial piece known to exist.

The example in our 25 September sale is scarcer still since non-invasive XRF testing has revealed that the coin is made from nickel-brass, an alloy of copper, nickel and zinc, otherwise known as nickel silver. Only a handful of other trial coins of this type, made from this specific alloy, are known to have been offered for sale, the latest in 2020.

Other 1981 trials sold recently are described as being made from cupronickel.

This nickel brass trial piece is expected to sell for between £500 and £700.

Feature Lots In Our September Sale

We are proud to offer this trial piece in our third specialist coin sale, building on our growing reputation for selling modern rarities including a mule error Kitchener £2 (sold £1,000 in February 2024) and a 'lines over the face' Aquatics 50p (sold for £1,500 in May 2024).

The trial coin is just one piece from an exciting catalogue that includes other premium modern issues from The Royal Mint, as well as an extensive range of high grade hammered and milled coinage.

Other significant modern coins going under the hammer on 25 September include:

• 1934 Silver 'Wreath' Crown - known as 'Wreath' Crowns for their distinctive obverse, this date is the rarest in this commemorative issue with only 932 struck. Estimate: £2,500-3,500.
• 2021 Gothic Portrait 5oz Gold - this 999 gold coin features William Wyon's classic design and is part of the sought-after Royal Mint Great Engravers collection. Estimate: £7,000-8,000.
• Bank Of China Coin Sets - two sought-after China Mint Company coin sets, dated 1981 and 1982 are offered complete in their original sleeves. Estimate: £400-600 (each).
• 1983 New Pence 2p In Set - this coin set produced by The Royal Mint and Martini & Rossi contains the rare mule 1983 2p which erroneously reads 'NEW PENCE'. Estimate: £600-800.
• 2009 Olympic Athletics 50p - a carded and an NGC graded version of this 2009-dated Olympics 50p are offered for sale: most Olympic 50ps are dated 2011. Estimate: £150-200 (each).

Are you looking to sell a Royal Mint trial piece, UK error coin or another rare modern numismatic item? Contact coins@rwbauctions.com today for quick, free valuations and reduced seller's rates, exclusive to our coin sales.