The top of your first pic has three symbols, two of which mean Nippon or Japan. There is also the symbol for 'yen' at the 5 o'clock position. Also lots of Japanese coins have a circular flower which is supposed to be a chrysanthemum.
Here are lots of examples on numista. Note the flowers or the Nippon symbols.
Your 10 yen is a little older and probably has a reeded edge. They are supposed to be harder to find and maybe a little more valuable than the ones with plain edges.
No easy references but after enough time you get to see patterns and can come pretty close to the country a coin is from. I may not know at a glance if a coin is from Taiwan or China, but I can tell that it's more likely from there than Nepal or Thailand. . .
Posted: Sat Mar 03, 2012 8:18 am