Trial pieces for British West Africa were produced in London, typically at the Royal Mint, to test alloy compositions before committing to full production runs. Tin brass was evaluated as a cheaper alternative to the nickel-brass and cupro-nickel alloys used in circulation coinage for the region — West African humidity and salt air accelerated corrosion in ways that made alloy selection genuinely consequential, not merely economical.
Trials from 1920 survive in very small numbers and were never released to circulation.
Trial pieces for British West Africa were produced in London, typically at the Royal Mint, to test alloy compositions before committing to full production runs. Tin brass was evaluated as a cheaper alternative to the nickel-brass and cupro-nickel alloys used in circulation coinage for the region — West African humidity and salt air accelerated corrosion in ways that made alloy selection genuinely consequential, not merely economical.
Trials from 1920 survive in very small numbers and were never released to circulation.