I am seeking data about Johann Anthonie ZWEKKERT, mintmaster in Sourabaya from 1807-1817.

I have Pridmore and Bucknill, both of which are helpful, but I can't determine his date of birth (Jafna in Sri Lanka) or details of where he trained as a Doctor, presumably for the VOC. He served as a master for Batavia, the French, the British, and finally the Dutch, and was highly thought of. He deserves a record. Any help would be gratefully received and appreciated.

When Java was taken by the EIC the Old Dutch mint at Sourabaya was restored and its Dutch mint master, Zwekkart reappointed to strike copper similar to Dutch designs, but using the EIC balemark instead of the Dutch one. The ½ stiver of 1811 is shown, obverse on left, reverse on right. The blanks were cast and issued each year from 1811 to 1815. They have a "z" for the mint master.