Arabic inscriptions and date: Sultan Palembang Sanat 1200 (retrograde 1200 AH = 1785 AD) / Blank. Struck on a cast tin flan. 18mm, 0.65 grams. Krause -; V.LaHaye/E.Spanier & Fils Lith Du Roi #191; Zeno 187181 (this coin).
Coins dated to 1200 are quite rare (much more so than the coins dated to 1202 and 1203). They are known only with a date written right to left.
Palembang is a city in the Northern area of Sumatra, Indonesia. It was once a Portugues colony, and later the seat of the Sultanate of Palembang. These coins used to be quite rare and expensive, until a number of large hoards made them generally available and relatively cheap. For example, coins of this type were sold by Münzen & Medaillen Deutschland GmbH, Auction 10 (March 22nd, 2002), #681. It was a lot of 3 pieces (same types as this coin and the same type of Badr-ud-din), sold for 120 Euros + auction commissions.