Why 17th Century Javanese Coins Found in Thames Mud?

This story told by Mr. Puji Harsono that the messenger from the Bantam Kingdom (Old Banten) ever came visited England in 1682. That's why the 17th century Javanese coins found in Thames mud.
Coins, Bank Notes, Antiques, and Books Collection. They are Pieces of History.

In the Djenggala era at Kediri which known as the oldest kingdom on Java Island, the money was called by name "Krishnala". The money was made of silver and bronze. In the Majapahit era, the money was known by name "Gobog", looks like the Chinese gobog. Form in thin-circle and there was a rectangle hole at its center. In general, the Gobog money has carved of animal, puppet, and the relief which symbolize a people tale on that time.
There is more in the Kingdom of Banten, the currency which has the form as like as the Majapahit's Gobog money. In the Kingdom of Sumenep, the money called by name "Real Batu". That money supposed come from the Kingdom of Spanish's currency, but modificated by put a stamp of Arabian character "Soemenep", "Number" or "Rose flower".