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

The Britannia silver bullion series was revised in 2007 to raise the fineness from .958 to a confirmed legal standard, coinciding with a broader Royal Mint effort to compete directly with the Canadian Maple Leaf and the American Silver Eagle in the international bullion market. The quarter-ounce denomination was introduced partly to offer lower entry-price fractional pieces to collectors unwilling to commit to the full one-ounce coin.

The .958 Britannia standard is historically derived from the old Britannia silver standard introduced in England in 1697 — briefly made compulsory for sterling silverware to protect coinage metal from being melted down by goldsmiths.