Karat (abbreviated K or kt) measures gold purity in parts per 24. Pure gold is 24 karat (24K). An 18K piece is 18 parts gold out of 24, or 75% gold by weight. 14K is 14 ÷ 24 = 58.33%. The system’s roots trace to medieval European trade: a 24-grain mark on a coin was used to indicate pure gold content, with the grain being a seed counterweight.
The karat system and its numeric hallmark equivalents (585 for 14K, 750 for 18K, and so on) are what you need to know to calculate scrap gold value, evaluate a buyer’s offer, or verify a piece you are selling or buying.
Karat purity table
| Karat | Purity | Common hallmarks | Primary use |
|---|---|---|---|
| 24K | 99.99% | 999, 9999 | Gold bars, Gold Buffalo bullion coin |
| 22K | 91.67% | 917, 916 | American Gold Eagle, Krugerrand, British Sovereign |
| 21K | 87.50% | 875 | Middle Eastern and Gulf jewelry |
| 18K | 75.00% | 750 | Fine jewelry, luxury watches, European pieces |
| 14K | 58.33% | 585, 583 | Most US rings, necklaces, bracelets |
| 12K | 50.00% | 500 | Uncommon; some vintage US pieces |
| 10K | 41.67% | 417 | Budget jewelry; minimum for “gold” in the US |
| 9K | 37.50% | 375 | Standard in UK, Ireland, and Australia |
In the US, the minimum purity that may be called “gold” without further qualification is 10K (41.67%), per the National Gold and Silver Stamping Act. In the UK and much of Europe, the minimum is 9K (37.5%).
FTC karat marking rules
The FTC’s Jewelry Guides (16 CFR Part 23) require that karat markings accurately represent the gold content. Misrepresenting karat fineness is an unfair or deceptive trade practice under 16 CFR 23.3.
The National Stamping Act (15 U.S.C. 295), referenced at 16 CFR 23.3(d), specifies narrow assay tolerances:
- Articles without solder: permissible tolerance of 3 parts per thousand (0.3%) below stated fineness
- Articles with solder: permissible tolerance of 7 parts per thousand (0.7%) below stated fineness
In practice: a 14K stamped ring without solder must contain at least 580 parts per thousand gold (58.0%) on assay. A 14K piece containing only 560 ppt (56%) would be a deceptive marking. The 585 stamp seen on European 14K pieces (rounding 58.33% to 58.5%) is actually slightly above the US standard, not below it.
These tolerances are narrow testing allowances, not a license to sell below-karat gold. Any seller who knowingly stamps 14K on a 13K piece is in violation of both the FTC guides and the National Stamping Act.
How karat affects scrap gold value
At spot gold of $4,134.80/ozt (October 7, 2026, gold-api.com), here is the melt value of a 10-gram item at each karat:
| Karat | Purity | Gold in 10g | Troy oz | Melt value |
|---|---|---|---|---|
| 24K | 99.99% | 9.999 g | 0.3215 ozt | $1,329.24 |
| 22K | 91.67% | 9.167 g | 0.2947 ozt | $1,218.63 |
| 18K | 75.00% | 7.500 g | 0.2411 ozt | $997.03 |
| 14K | 58.33% | 5.833 g | 0.1875 ozt | $775.28 |
| 10K | 41.67% | 4.167 g | 0.1340 ozt | $553.95 |
The same 10g piece of jewelry is worth $221 more at 18K than at 14K — a difference that compounds significantly over a larger collection.
Per-gram melt values at October 7, 2026 spot:
- 10K: $55.39/g
- 14K: $77.55/g
- 18K: $99.70/g
- 22K: $121.86/g
- 24K: $132.94/g
Check today’s figures with the Scrap Gold Calculator, which updates with live spot prices.
Worked example — 5g 14K gold ring
Weight: 5.00 g (on a scale reading to 0.1g)
Karat: 14K → 14 ÷ 24 = 0.5833 purity
Gold content: 5.00 × 0.5833 = 2.917 g Au
Troy oz: 2.917 ÷ 31.1035 = 0.0938 ozt
Melt at $4,134.80/ozt: 0.0938 × $4,134.80 = $387.84
At 80% dealer payout: $387.84 × 0.80 = $310.27
At 90% refiner payout: $387.84 × 0.90 = $349.06The payout percentage matters as much as the karat. For the same ring, the difference between a 70% pawn-shop offer ($271.49) and a 90% refiner offer ($349.06) is $77.57.
Reading gold hallmarks
Numeric hallmarks (thousandths fine) are standard in European and international trade and appear on many pieces sold in the US:
| Stamp | Karat | % gold |
|---|---|---|
| 999 or 9999 | 24K | 99.9% or 99.99% |
| 958 | 23K | 95.8% |
| 917 | 22K | 91.7% |
| 750 | 18K | 75.0% |
| 585 | 14K | 58.5% |
| 417 | 10K | 41.7% |
| 375 | 9K | 37.5% |
| 333 | 8K | 33.3% |
Karat letter marks: “14K,” “18K,” “14KT,” or “14 Kt.” These appear on older US pieces and are equivalent to the numeric stamps.
Filled and plated gold is distinct from solid gold:
- “GF” or “1/20 14K GF” = gold-filled: a thick layer of 14K gold bonded to base metal; the gold layer must be at least 1/20th of total weight per 16 CFR 23.3(c)(2). Gold-filled material has recovery value but requires specialist refining.
- “GP,” “HGP,” “HGE,” “GE” = gold plated or electroplated: a thin surface layer (minimum 0.175 microns of fine gold per FTC rules), negligible scrap value.
- “RGP” = rolled gold plate: thin bonded layer, similar to gold-filled but thinner (at least 1/40th of total weight).
If a piece lacks any stamp, it warrants testing before you assume it is solid gold. Acid test kits or XRF analysis at a coin shop can confirm karat.
Testing karat at home
Magnet test: Gold is not magnetic. A piece that sticks firmly to a strong magnet contains ferromagnetic material (iron, steel) and is not solid gold. Note: this is a negative test only — gold-plated steel will also repel the magnet on the surface while the steel core attracts it.
Acid test: Testing kits include bottles of nitric acid labeled for 10K, 14K, and 18K. A drop on a fresh scratch of the metal produces a color reaction that indicates approximate karat. Commercial kits run $20–$60 and reliably sort rough categories. For precise assay, XRF (X-ray fluorescence) analysis at a coin shop is faster and more accurate.
XRF analysis: Many coin dealers and refiners offer free or low-cost XRF testing. The device reads the metal composition non-destructively in seconds and gives an accurate karat reading. This is the best option before selling anything significant.
See how to test gold at home for a step-by-step guide to each method.
What dealers pay for scrap gold by karat
No buyer pays 100% of melt — refining and overhead are real costs. Typical payout percentages vary by buyer type. Check current dealer listings for live rates, as these shift with competition and market conditions:
| Buyer type | Typical payout range |
|---|---|
| Specialist online refiner (mail-in) | 85–92% of melt |
| Local coin dealer | 75–85% of melt |
| Local jeweler | 70–80% of melt |
| Cash-for-gold kiosk | 50–65% of melt |
| Pawn shop | 40–60% of melt |
Higher-karat pieces (22K, 24K) often get slightly better payout rates because they require less refining effort. Mixed batches of 10K, 14K, and 18K are less efficient to process and may attract lower percentage offers from some buyers.
Use the Scrap Gold Calculator to calculate melt value, then the Dealer Payout Calculator to evaluate any offer before you sell. Compare at least three buyers — the spread between the lowest and highest offer for identical gold is routinely 15–20%.