2 Dollars - Elizabeth II 1931 Matchless Silver Hawk

The "1931 Matchless Silver Hawk" commemorates the Supermarine S.6, the British seaplane that won the Schneider Trophy race that year at a speed exceeding 340 mph — a record that directly informed the aerodynamic calculations behind the Spitfire's elliptical wing design. Reginald Mitchell engineered both aircraft, and the S.6's Rolls-Royce engine program was the direct predecessor to the Merlin.

Cook Islands became a prolific vehicle for themed bullion issues in the 2000s through licensing arrangements that kept production costs low while allowing private mints to reach collectors under a legitimate sovereign issuer. KM#517 is one of dozens of such issues from this period.