1997 mint error £2 coin, struck on a complete nickel-brass blank:
Obverse: ELIZABETH II DEI GRATIA REGINA F D ; around portrait of Queen Elizabeth facing right, wearing a pearl necklace.
Reverse: TWO POUNDS 1997 ; four concentric circles radiating outwards from the centre of the coin, symbolizing mankind's extraordinary drive, determination and creative genius. The central disk represents the Iron Age and when the coin is tilted a metalwork pattern of whorls is clearly seen; the first ring with its arrangement of cogs, gears and wheels, represents the explosion of industrial development which is now referred to as the Industrial Revolution. the second ring has a pattern derived from a silicon chip and the outer ring represents the age of the internet and the information superhighway.
Edge: Milled with the incuse inscription STANDING ON THE SHOULDERS OF GIANTS.

In 1997 a new design was produced for circulation. It was the first bi-metallic coin issued in the UK since the tin farthings with a copper plug in 1692. Due to technical difficulties the new coins were not released by banks until the middle of 1998.

The new £2 coins were to be struck from two separate blanks, an inner cupro-nickel disk and an outer nickel-brass ring. The outer portion starts its life as a complete disc and prior to the striking process has its central portion punched out leaving only the outer ring. The cupro-nickel disk and nickel-brass ring are then fed into a coining press at the same time and are bonded together at the time of striking. In this case, for some reason, a complete nickel-brass blank found its way to the coining press and was struck by the £2 dies in the usual way.

This coin is an example of an extremely rare minting error and is especially pertinent due to these coins being meant to be the first bi-metallic United Kingdom decimal coins.