I recently saw an add for $1000 face value for pre-1965 silver.  The add included "pre-1965 90% Washington Quarters almost all and very few Standing Liberty quarters or barbers."

How do you figure out the actual current value, given spot price?

www.coinflation.com

There is no percentage of spot price or anything that governs the price of junk silver. It is typically <5% above spot (in quantity), but there have been times in the last decade when it was very close to spot. It all depends on supply and demnad. There have also been times when demand has made the premium for junk silver a lot more.

There is about 715 troy ounces of silver in $1000 FV of junk silver. Spot silver is a few cents shy of $14 right now. So $1000Fv of junk silver is worth about $10,000 if valued at spot prices. Right now the going rate is about 50 cents over spot for larger quantities, so you could expect to pay perhaps $10,370. Some places will be a little more. In smaller quantities (like $10 FV), I would expect to pay perhaps 11-12X face right now.

http://lynncoins.com/jsilv.htm this site says those Standing Liberties are $165 per 20 right now = $8.25 each. So, $1000 face value is 2000 coins. That's $16500.

I second the 10-12X face value for pre-'65 U.S. dimes and quarters in bad condition.  In bulk, you may find them for a little less.  Silver dollars in decent shape seem to carry a premium, and its hard to find one for less than $15.

Face value times .72 * sopt price of silver = the value of the silver in the coin if the coins aren't worn. Some dealers use .715 or .710 to allow for wear.  OTOH, since the coins are impure, thay are worth less if melted, but some people see them as an attractive vehicle for "hard money" investing.  And even generic silver rounds cost a bit  to make.

Where the value ends up ends up being a pulling match between the low melt value, and the desire from investors wanting "hard money" (Serious silver investors buy 1000 oz bars or pool accounts which hold bars for easier inventory)

WSJ actually publishes a wholesale price for bags ($1000 face)  you can see where they fall out vs soilver bullion.  When the economic outlook is bearish, Krands, eagles and bags go past the spot price of silver.  When metals are weak, junk silver usually retreats below spot, Krands close to spot,  and eagles usually still hold a premimum.  I dount anyine ever melts junk silver, when the prices falls below spot, it probally encourages dealers to push it instead of rounds.