Clint Siegner, a Director at the Money Market Exchange, has revisited his article about 90% U.S. Silver coins.  Junk Silver quarters were made until 1964 when the US mint switched over to copper-nickel alloy.  Along with junk silver dimes, they are one of the most affordable ways to buy silver bullion. There are three designs of silver quarter coins still widely available.  The “Barber” was introduced in 1892.  The “Standing Liberty was minted from 1916 to 1930. The “Washington” was minted from 1932  to 1964 until the US Mint switched over to the Copper-Nickel alloy in 1965.  All of these coins up to 1964 were made with 90%silver and10% copper and have a silver content of 0.179 troy ounces of silver.  The link below with direct you to the complete article which goes into much great detail of the history surrounding the various issues.  Money Metals Exchange also offers junk silver at very affordable prices.

Junk Silver is a term used to denote silver coins that are in usually poor to fair condition and are priced accordingly depending upon the current market.  However, demand from numismatic collectors is another issue.  Just like other 90% silver, dimes and half dollars, there is a special market for these rarer coins in much nicer condition and the value can be very high.

There are special publications issued yearly and monthly that go into much greater detail regarding the different years of issue.  Follow this link to Captains Coins.  You will find many items listed and they change continually.

Source: Silver quarters: The Ultimate Guide to What Quarters are Silver – Money Metals Exchange