u/X8883

Copied from ancientcoins sorry

I bought some coins from an expo yesterday. They were placed in a small ziploc for about 36 hours. 24 hours ago, they all looked completely fine.

Now, I noticed a white substance on one of them. I immediately took all coins that I saw any white away, they are in the photo. However none of the white was actually able to be disturbed (I used a mechanical pencil) on any coin except the second photo in the slide. What next? I'm very concerned.

I seperated the coins on the second, third and fourth slides and the rest from the ones that had no white on them, and double sealed everything in fresh ziplocs. I will immediately move to 2x2s or saflips when I get home in 3 days.

I am leaning to Vietnam, but that is only based off of the very circular boo, and the fact I know they've made 180 degree errors in the past. It could easily be Chinese too; the Vietnamase Canh Long Thong Baos are less crude than this usually IIRC. I doubt it's Indonesian because while the characters are crude they are still pretty faithful to how they should look. Any opinion is appreciated.

If it is not Balinese let me know but this type is known to people in these circles as from Bali area, they tend to imitate Chinese characters but some are written in the Balinese language like this one.