Saint Helena is a small island in the South Atlantic Ocean which is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha. The currency of the island is the Saint Helena Pound, fixed at parity with the Pound Sterling. The island has been issuing commemorative coinage since 1989, initially mostly in the British Crown format.
The United Kingdom pre-decimal Crown denomination was equal to 5 shillings, which was re-denominated as a 25p coin at decimalisation in 1971. For that reason, commemorative crowns were initially denominated as 25 pence - which was written on the Saint Helena coinage, unlike its British counterpart which for a long time had a tradition of not spelling out the face value on the coin. After 1990, the "Crown" was revived as a commemorative £5 (five pounds) coin in the UK, with each issue usually having two versions - one in copper-nickel and one in silver.
Saint Helena Crowns have the same specifications and face value as the United Kingdom denomination, but are legal tender in the territory only and not in the UK. The coins are "Non-Circulating Legal Tender" (NCLT) and not bullion because they are issued at prices much higher than their bullion value and are targeted at collectors who appreciate them for their artistic or sentimental value, and not at bullion investors.