Royal Arms £1 (1983 to 2008)

The year matters first. The 1983 coins were struck in huge numbers to replace the note, so worn ones are common, while 2008 had the smallest circulation run of the Royal Arms years. Coins dated 1998 were never issued for circulation and come only from collector sets. After that comes grade: the lion, the unicorn and the mottoes wear quickly, so a sharp coin sells well above a tired one. Coins from the 1983 brilliant uncirculated folder and the 2008 pack for the coin's 25th anniversary sell above coins from change.

With 623,304,510 struck for circulation, the Royal Arms £1 is the 25th rarest of the 26 ranked £1 designs and has the 178th lowest mintage of all 194 circulating UK designs. That puts it in the Common band, for mintages 10,000,000 or more.

The next rarer £1 is the Leek £1, with 325,700,051 struck, and the next more common is the Nations of the Crown £1, with 1,753,082,905 struck.

Its lowest circulation mintage was in 2008, with 3,910,000 struck.

Look for the full Royal Arms: a quartered shield held up by a lion on the left and a unicorn on the right, with DIEU ET MON DROIT on a scroll beneath and ONE POUND along the bottom. The edge reads DECUS ET TUTAMEN. To tell the years apart, check the heads side: 1983 has Arnold Machin's portrait, 1993 Raphael Maklouf's, and 1998, 2003 and 2008 Ian Rank-Broadley's. Timothy Noad's 2015 Royal Arms looks similar but adds four national flowers below the shield.

The round £1 coin was issued on 21 April 1983 to replace the Bank of England £1 note, which stopped being issued at the end of 1984 and was withdrawn in March 1988. Its reverse was chosen by competition, judged by the Royal Mint Advisory Committee, and the design selected was by Eric Sewell, a former chief engraver of the Royal Mint. He chose the full Royal Arms: the quartered shield, the lion and the unicorn as supporters, the Garter motto HONI SOIT QUI MAL Y PENSE around the shield and DIEU ET MON DROIT on a scroll below. The edge reads DECUS ET TUTAMEN, meaning an ornament and a safeguard, a motto that first appeared on the machine-struck coins of Charles II, where the lettering protected the edge from clipping. The milled edge also carries the cross crosslet mint mark for Llantrisant, and this was the first United Kingdom coin to bear it. The Royal Arms came back as the United Kingdom design in 1993, 1998, 2003 and 2008, under three different portraits of the Queen.