Once I knew a programmer who was Chinese and hated programming. He wanted to be in security. He was going over the code for his program. He always said "empty" like "empa-tee". His name was Alex. He was there the day that I discovered the Chinese Silver Dollar coins in the import/export shop downstairs. I bought a page of silver dollars - eight for six dollars. Go figure. The next day I went back because I collect coins on the side. There was another page available for six dollars. I bought it and then asked if he had more. He had more. In the end I got about 8 pages of 8 coins.
I showed them to Alex, who was also a bit of a Chinese history buff. He told me about each of the dynasties represented by the coins. I forget it all now, but one thing he noticed was that there were chop marks on the coins and he said this was good. It was good because it proved that the coins were authentic. He said there were two ways commonly used to prove the authenticity of coins - one was to whack it with a huge chopper. If the coin survived, it was real. The next way was a bit more civilized and sophisticated and required a good ear. He demonstrated for me. He took a silver coin and held it in the middle of the coin between two fingers, then blew in an expert fashion hard on the edge, then quickly put the coin up to his ear as if listening to a tuning fork. If you can hear a ringing, it is real. I tried it, but could not get it to ring. I think it is in the angle and strength of his blowing. He did it for me and put it up to my ear and I could hear a small ringing.
When Alex got another job, I gave him one of the pages of chinese silver dollar coins. He was very grateful because he appreciated their historical value. He was the only one who actually appreciated them other than me and he did help me figure out his spaghetti code before he left. Thanks, Alex.
Oh, yeah, after he left, I checked eBay and found that back then one of the coins sold for $7.99. So, I spent $48.00 for 56 coins and if each of them is really worth about $8.00 each, then each page is worth that much and I made a bit of a bundle on that deal - not even including the historical significance of the coins.