25 Gulden

De Javasche Bank, the colonial central bank of the Dutch East Indies, issued this series during a period when the gulden's convertibility was still tied to the gold standard — the Netherlands held that peg until 1936, meaning these notes circulated under a relatively stable monetary regime by the standards of the region and era. Enschedé in Haarlem had printed colonial currency for Dutch possessions for generations; their intaglio work on this series is characteristically dense and precise.

The watermark is the primary anti-counterfeiting measure — no metallic thread, no complex overprint. Simple by later standards, but sufficient for the period.