My great-grandfather bought this 18 carat gold pocket watch in the former Dutch East Indies, today of course known as Indonesia. I think he must have bought it somewhere in the twenties or thirties. The text on the dial says 'Chronomètre Perla, A. Schönmann, Soerabaja'. I am guessing the first is the brand name, the second the jeweller's name. The third is a city in the former Dutch east Indies. Can anyone tell me something about this watch? I am a complete amateur in this still.. I included pictures of teh watch and its movement. Thanks!!