From http://en.wikipedia.org/wiki/Coinage_Act_of_1834#cite_ref-7
The Coinage Act of 1834 was passed by the United States Congress on June 27, 1834. It raised the silver-to-gold weight ratio from its 1792 level of 15:1 (established by the Coinage Act of 1792) to 16:1 thus setting the mint price for silver at a level below its international market price.[1][2] After its passage, one ounce of gold was the equivalent of $20.67.
and
After the Coinage Act of 1834, silver (which was previously overvalued with respect to gold) became significantly undervalued and was exported to European markets where it was traded at a higher price.[7][8] This led to its near disappearance from par-circulation after 1834.
So my thoughts are would this mean that there would be a greater chance of finding pre 1834 silver coins in Europe than the US are did they all get melted down in Europe ? Also it looks to me also making money from coins go backing a long time in the USA.