I received this coin from a friend. Unfortunately, I tend to collect modern and common coins, so this is definitely not within my area of knowledge. I believe it to be a 1 Pitis coin from Palembang, present-day Indonesia (specifically this https://en.numista.com/catalogue/pieces109644.html) but I can be wrong.


The diameter of the coin at its narrowest is 20 mm. At its widest, it's 20.4 mm. Unfortunately, I don't have a weighing scale for coins or jewelry. I also checked this article by Frank S. Robinson on Palembang coins (http://www.fsrcoin.com/palembang.html) and they seem to be identical. Of course, I may also be wrong with my observations and a second opinion is definitely welcome.
I'm wondering if this coin is authentic or counterfeit. Would be glad to hear your thoughts on this!
(Also, please do notify me if I posted this in the wrong forum. Thank you!)