During the 1980 Nelson Bunker Hunt silver mania you couldn’t get shtye for your junk silver. The silver content in it was deeply discounted if you brought it to a gold dealer to sell. What the gold/silver buyers wanted was pure silver with 100oz silver bars preferred. There were few if any 100% silver coins back then. Today (of course) there are very good ones from the Canadian and US governments and other places. I would trust an APMEX one ounce silver coin (rounds is what they are called) or same size APMEX silver bar. Or the 10oz APMEX silver bar. They are stamped out hard like a coin so look very nice and acceptable in a SHTF situation or just in trade next week to buy stuff. Not poured like ye old 10oz silver bar by Engelhard or Johnson Mathey you can find on eBay.
POURED
LOAF
INGOT
http://www.ebay.com/sch/i.html?_odkw=johnson+matthey++10&_osacat=0&clk_rvr_id=457466044968&_from=R40&_trksid=p2045573.m570.l1313&_nkw=engelhard+10&_sacat=0
In 1980 your junk 90% silver coins....Lets say the dealers would buy the silver content of them at about 60% of its value. It was in that area
And then there is always the worry this could happen again.
http://en.wikipedia.org/wiki/Executive_Order_6102