Backstory: I am a bank teller and we have a coin counting machine in our vault. It has a reject bin that we occasionally pick through when it fills up, and sometimes it has come pretty cool stuff in it. Well I was looking through it the other day, and found what is now the oldest coin in my collection. This 1870 Dos Centimos coin from Spain. I'm not really a foreign coin collector at all, but I really love this coin. Beautiful designs front in back, and it's the thinnest coin I have ever seen as well, just .7 MM thick. I seriously could not believe my luck pulling a 145 year old coin out of that thing. Here are some pictures:

