50 Pence - Elizabeth II 4th portrait, 1/4 oz Fine Silver

The Britannia silver bullion series, launched in 1997, used .958 fineness — Britannia silver — rather than the more commercially common .999, a deliberate nod to the historic sterling standard's near-equivalent and a way of distinguishing the British product from the Austrian Philharmonic and Canadian Maple Leaf then dominating the bullion market. By 2001 the series had found a modest but loyal collector base, though it never seriously threatened the market share of those competitors.

The fourth portrait of Elizabeth II, by Ian Rank-Broadley, had been introduced on circulating coinage in 1998 and carried over to this series shortly after.