These items are known by various names in English: "Islamic tokens", "pilgrim tokens", "Hajj tokens" and "magic coins" are all terms I've seen used to describe them. Intended originally as tokens to give to pilgrims on their way to Mecca, as inspirational reminders of the reason for their long journey, they are nowadays mass-produced and sold to both locals and tourists as lucky charms, particularly in some parts of Indonesia.
This section of the zeno.ru Asian coin database illustrates numerous types and designs of these pieces.
If your piece is old, it might be one of the earlier silver ones, though the design of this piece does not look "old" to me; modern ones are usually quite brassy. You might want to get it tested by a jeweller to see if it is silver. Older ones can be valuable, though finding a collector that is knowledgeable enough and interested enough to pay a high price for one is not easy.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis