1 Double

Guernsey's doubles — a denomination unique to the island and entirely outside the British sterling system — were struck in a denomination that traced back to local Norman custom, with the double equivalent to one-eighth of a penny. The States of Guernsey jealously guarded the right to issue their own coinage, a privilege periodically contested by the British Treasury and just as periodically reaffirmed by the island's own legislative body.

The KM#10 series ran across four monarchs' reigns without meaningful redesign — a telling sign of how little London's succession politics mattered to Guernsey's domestic currency arrangements.