4 Keping Thick flan

The 4 Keping was struck at the Soho Mint in Birmingham under Matthew Boulton's steam-powered presses — the same facility responsible for reforming British domestic coinage. The East India Company contracted Boulton specifically because local Straits production had been plagued by counterfeiting, and the mechanical precision of Soho made imitation considerably harder.

The thick flan variety is distinguished from the thin flan striking of the same year by a noticeably greater planchet depth, a consequence of differing blank preparation runs rather than any deliberate denomination distinction.