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Guides
Short guides and the free lookups buyers use: what to check, key marks, red flags, and where to verify certificates and sold prices.
Coins
How to size up coins at auction.
Open guide →Bullion and metals
Bullion and precious metals at auction.
Open guide →Gold and jewelry
Gold and jewelry at auction.
Open guide →Sports cards
Sports cards at auction.
Open guide →Stamps
Stamps at auction.
Open guide →Collectibles and antiques
Collectibles and antiques at auction.
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Reference
Metals price and melt reference
How melt value is calculated
Melt value = weight (troy ounces) × purity × spot price per troy ounce
If you have grams: troy ounces = grams ÷ 31.1035. Example method: a 10 grams 14 karat (14K) ring holds 10 × 0.583 = 5.83 grams of gold, or 5.83 ÷ 31.1035 = 0.1875 troy ounces. Multiply by the current spot price.
Melt is metal value only. Dealers and refiners pay less than full melt.
Common purities
| Mark | Purity |
|---|---|
| .999 fine (bullion) | 99.9% |
| .925 sterling silver | 92.5% |
| .900 coin silver | 90.0% |
| 10 karat (10K) gold (417) | 41.7% |
| 14K gold (585) | 58.3% |
| 18 karat (18K) gold (750) | 75.0% |
| 22 karat (22K) gold (916) | 91.7% |
| 24 karat (24K) gold | 99.9% |
Weights
| 1 troy ounce | 31.1035 grams |
| 1 pennyweight (dwt) | 1.5552 grams |
| 20 dwt | 1 troy ounce |
| 1 ordinary (avoirdupois) ounce | 28.3495 grams |
| 1 kilogram | 32.1507 troy ounces |
Silver in United States 90% coins (dated 1964 and earlier)
| Coin | Total weight | Pure silver |
|---|---|---|
| Dime | 2.50 grams | 0.0723 troy ounces |
| Quarter | 6.25 grams | 0.1808 troy ounces |
| Half dollar | 12.50 grams | 0.3617 troy ounces |
| Morgan or Peace dollar | 26.73 grams | 0.7734 troy ounces |
| $1 face value of dimes, quarters or halves | 0.7234 troy ounces (about 0.715 when worn) |
Also: 1965–1970 Kennedy halves (40% silver) hold 0.1479 troy ounces; 1942–1945 war nickels (35% silver) hold 0.0563 troy ounces.
No live prices here. For spot, see Kitco or the London Bullion Market Association (LBMA) benchmark prices.
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