4 Dollars - Elizabeth II SML fractional set, 1⁄2 oz

The SML fractional sets — Small, Medium, Large — were introduced by the Royal Canadian Mint in the early 2000s as a way to sell fractional silver in matched presentation sets rather than as standalone bullion. The four-dollar denomination on a half-ounce piece is an artifact of that packaging logic, not a reflection of any circulating monetary unit. Canada has never issued a four-dollar coin for general circulation.

.9999 fine silver was the RCM's calling card for this era, giving it a purity edge over the standard .999 used by most competitors at the time.