The least glamorous name in coins hides the simplest math in the hobby.
The least glamorous name in the coin world attaches to some of its most honest metal. "Junk silver" is a trade nickname, not a judgment, and behind it sits the simplest, most useful math in the entire hobby.
Junk silver is the trade term for circulated, common-date U.S. dimes, quarters, and half dollars struck in 90 percent silver before 1965, coins valued for metal content rather than collectible rarity. The name arose among dealers sorting coins with no numismatic premium, and it stuck because it is efficient, not because the silver is anything less than real.
As minted, one dollar of face value in 90 percent coins contained about 0.7234 troy ounces of pure silver, a figure fixed by law when the coins were designed. Decades of circulation wore a whisper of metal from every coin, so the market convention values circulated 90 percent coinage at roughly 0.715 troy ounces per dollar of face value. That small haircut for wear is the entire difference between the mint’s number and the market’s.
The formula is one line: face value × 0.715 × the current silver price. Ten dollars face is about 7.15 ounces; a hundred dollars face is about 71.5. The trade often moves this material in standardized $100 and $1,000 face-value bags, and dealers quote it as a multiple of face, which is just the same formula wearing work clothes.
Two families follow their own numbers. War nickels of 1942 to 1945, identified by the oversized mint mark above Monticello, are 35 percent silver, about 0.056 troy ounces each. Kennedy half dollars of 1965 through 1970 are 40 percent silver, about 0.148 troy ounces each. Everything else in modern change contains none, a story told fully in Which US Coins Contain Silver.
Ninety percent coinage offers something bars cannot: recognizable, government-struck silver in small, divisible pieces with a design history attached. A Mercury dime is bullion that is also a small piece of 1940s America. That dual character, metal plus memory, is why the least glamorous silver in the case remains one of the most steadily requested.