Silver in foriegn coins

People that traveled the world, especially those who fought in wars, have stashes of foreign coinage.  Most of the time we see coins that were simply currency at some point, and are not rare.  We do see the occasional rare foreign coin, but it's not the norm.  Most coin dealers pay by the gram, or by the pound.  What some dealers don't tell you, is that there is silver in some of the coins you are selling for 1 penny a gram.  One of the things that separates us, is that we tell you when you have silver.  Not only do we tell you, we pay you a fair price for it.  One way to check your foreign coins for silver content, is to drop them one by one on a hard surface.  Non-silver coins tend to make a "thud" sound, whereas silver coins tend to make "ting" sound.
We look forward to appraising your foreign coins!