Can anyone help me ID this Chinese Coin? After taking it to a few friends at Chinese Restaurants, I have narrowed this down to a Jia Ching 1793-1820. Any Ideas to it's authenticity or Value? (or if what I heard is true?) It measures 24mm. Also see this post for the story on how I almost trashed this coin http://forum.treasurenet.com/index.php/topic,216838.0.html (about 6 replies down). Also help on IDing Tinman's find would be great too! Thanks!