Guides · Gold and jewelry
Gold and jewelry
Gold and jewelry at auction: karat stamps, hallmarks, red flags, and free gem certificate and spot price lookups.
What to check
- Karat or fineness stamp (10K/417, 14 karat (14K)/585, 18 karat (18K)/750, 22 karat (22K)/916) and a maker's mark.
- Weight in grams; for scrap, melt is grams × purity × spot ÷ 31.1035.
- Stones: real gems add value, but most auction lots are priced on metal.
- Lab certificates for diamonds: check the number with the lab.
Key marks and dates
- 10 karat (10K) = 41.7% gold; 14K = 58.3%; 18K = 75.0%; 22K = 91.7%; 24 karat (24K) = 99.9%.
- Sterling silver is .925 (stamped 925 or STERLING).
- Gold Filled (GF), Gold Plated or Gold Electroplate (GP/GEP) and Rolled Gold Plate (RGP) are not solid gold.
- "Mixed 14K" lot weights can include stones, clasps and steel parts.
⚑ Red flags
- No stamp, or a stamp on a clasp only.
- Weights that include stones or non-gold parts.
- Certificates from unknown labs, or numbers that don't verify.
- Heavy, bright yellow pieces priced at karat value with no stamp.
Common fakes: jewelry and gold →Sourced screening tips.
Free lookups
Gemological Institute of America (GIA) ↗Look up a GIA diamond grading certificate on the GIA site.International Gemological Institute (IGI) verification ↗Check an IGI certificate number.Online Encyclopedia of Silver Marks ↗Identify silver and gold hallmarks.Federal Trade Commission (FTC) Jewelry Guides (Title 16 Code of Federal Regulations (CFR) Part 23) ↗United States rules on karat and fineness marking.Kitco spot prices ↗Live gold, silver, platinum and palladium spot.eBay sold listings ↗Search completed sales, not asking prices.
These guides are general information, not appraisals. Links go to independent sites we don't control and aren't affiliated with.
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