1/2 Hau - Taufa'ahau Tupou IV Coronation

Tonga's 1967 coronation coinage was among the first palladium issues produced by any government in the world, predating the widespread sovereign use of the metal by decades. The decision to strike in palladium was a deliberate commercial gamble by the Tongan government, working with the coin dealer Pinches of London, to stimulate collector demand through novelty of metal rather than novelty of design.

Palladium's spot price was highly volatile through the late 1960s, which made the series financially unpredictable almost immediately after release.