If, and only IF, they made a coin using pure silver, the total weight is major than if they made it using 80% silver and 20% copper. explain the overweight, but I will make some tests on this coin to verify how much silver was used on it. Besides that, I have assumed the risk when I bought (responding to @wcoins ).
Yes, that's the real weight of coin from switzerland mintage. 26.7g or, in my case, 26,4g means fake coin.
I bought from a Brazilian antiques seller that announced on internet. He isn't a coin collector and sell a lot of ancient things. So, I have assumed the risk when I bought. He thought that coin really was a silver coin. My guilt for don't verify all data of that coin or, at least, the wheight.
every coin collector has been burned on a coin so don't feel to bad. if you are really into world coins I would recommend you buy a Krause world coin catalog in the years you are collecting. you can buy used ones on Ebay for cheaper than new ones.
Good idea, but i'd really like to say I bought that coin for impulse, because was beautiful and was cheap. I'm disappointed because it's fake, but still like her. When I'll can I'll purchase another one like that, but original. E now I know that probably will be very spensive. That is what mean to be a coin collector, isn't?