Just to add to Siegfried's comments. Almost 100% of coins minted in China, Korea, Japan, and (perhaps) Annam - VietNam - were holed, prior to the very late 1800's. Common story in all of these countries is that they were, indeed holed to put some kind of small rope, though them, and then they would be hidden under the long outer-flowing garments that were commonly worn in each of the countries. I think that that is mainly true, but it does not account for the many single-dropped holed coins that I find when THing in Korea. Only thing I can think of is that only the very wealthy had enough to put on a stringer, and the poor joes would put their single or several coins in whatever kind of pocket they had available. (Maybe MaMa would only let Dad out of the house with a few coins, so he couldn't get in too much trouble.....like my wife does me.
)
It wasn't me, but another hunting buddy who did find a stringer of coins in the hills....kind of stuck together, just as we see pieces of metal
stick to other pieces of metal when left in the ground for a long period of time. He took time to slowly soak them in lemon juice, and let the citric acid do the trick.....a cleaning method I still use. He had a stringer of 56 of the larger denomination-2 coins....an average of 32 or 33 mms in diameter. All were Korean coins except one, and dated from the mid-1600's to the mid-1700's. The one was a huge Chinese coin, about double the size of the smaller Korean coins, and it dated about 1,000 a.d.......a truly great find.....and I could have killed him.
Been jealous ever since.
Why coudn't it have been me?