How We Calculate

The formula

Melt value = weight × fineness × spot price. Weight is converted to troy ounces (1 ozt = 31.1035 g; 1 dwt = 1.55517 g; 1 avoirdupois oz = 28.3495 g). Fineness is the fraction of the mass that is precious metal. Spot is the live per-troy-ounce price.

Spot prices

Live rates come from gold-api.com (gold XAU, silver XAG, platinum XPT, palladium XPD, copper HG per pound), fetched through our own cached endpoint and refreshed on page load. Each page also carries a build-time snapshot with its date printed under every table, so numbers remain meaningful even if the live feed fails. We show the quote timestamp rather than pretending prices are continuous.

Purity constants

Karat fineness is definitional: karat/24 — 24K = .999 (commercial fine), 22K = .9167, 18K = .750, 14K = .5833, 10K = .4167, 9K = .375. Silver: .999 fine, .925 sterling, .900 coin silver, .800 continental. Platinum: .950 for PLAT/PT950 jewelry. Actual alloys vary within legal tolerances; we use the nominal marks because that is how items are bought and sold.

Coin contents

US coin silver and gold contents use U.S. Mint historical specifications: 90% silver coinage at 0.7234 oz of silver per $1 face (0.7734 oz per dollar coin due to its heavier standard), 40% Kennedy halves at 0.1479 oz, war nickels at 0.0563 oz, classic gold at 0.04837 oz per dollar of face. Junk-silver lots use the trade convention of 0.715 oz per $1 face for circulated coins — the mint figure minus average wear. Copper cents (1909–1982) are counted at 2.95 g copper each (3.11 g × 95%).

Payout ranges

Where a page shows payout context (pawn 40–60%, jeweler 60–80%, refiner 85–95% of melt), those are typical published ranges for the US market, not quotes. Coin and bullion dealers sit between jewelers and refiners at roughly 75–95% depending on product — tightest on junk silver and bullion, wider on mixed scrap. Real offers vary with lot size, assay cost, and spot volatility. We show them because an offer is only judgeable as a percentage of melt.

What we deliberately don't do

We do not estimate collectible (numismatic) premiums — those depend on date, mintmark, and grade, and pretending a formula can price them would be dishonest. Where a coin type routinely carries premiums, the page says so and points you to check a price guide before selling at melt. We also don't price gemstones, gold-filled, or plated material, whose recoverable metal rounds toward zero.

Legal note on melting

Melting US 1-cent and 5-cent coins is prohibited under 31 CFR Part 82. Melt value for those pages is a metal-content benchmark — the basis on which sorted copper cents and war nickels actually trade — not an instruction.