½ Dollar - Elizabeth II Endeavour

Cook Islands has issued commemorative coinage under its own authority since 1972, despite having no independent currency in daily circulation — the New Zealand dollar serves that function entirely. The Endeavour series draws on Cook's 1769 Pacific voyages, but by 2015 the islands had spent decades producing low-mintage issues in unusual alloys primarily for the collector market rather than any transactional purpose. Billon at .333 fineness sits at the low end of silver content, historically a composition associated with fractional coinage under fiscal pressure rather than commemorative intent.