20 Dollars - Elizabeth II Eagle Feather

The "Eagle Feather" belongs to a long-running RCM fine silver $20 series that exploited a pricing loophole effectively: by issuing collector coins at face value — twenty dollars — the Mint sidestepped certain retail tax obligations for buyers, a strategy it ran aggressively through the 2010s before quietly retiring the approach. Mintage on individual issues in this series routinely sold out within weeks of announcement, driven almost entirely by domestic subscription lists rather than secondary market demand.

The .9999 fineness is worth noting — finer than the standard .999 used by most sovereign mints for bullion, and a specification the RCM has used as a consistent differentiator since the 1980s.