How We Test Gold
A transparent look at the testing process behind every gold offer we make.
Understanding Karat Markings
Gold purity is measured in karats, out of a possible 24: 24k is 99.9% pure gold, 18k is 75% gold, 14k is about 58.3%, and 10k is about 41.7%, the minimum legally sold as “gold” in the U.S.
How We Test Your Gold
Visual inspection starts with any karat stamps or hallmarks, which we then verify with testing. Acid testing uses solutions calibrated to specific karat levels on a small, unnoticeable area. Electronic and XRF testing measures metal composition without damaging the item at all for higher-value pieces. Once purity is confirmed, we weigh your item precisely and calculate your offer from the actual pure gold content at the current market price.
What About Gold-Plated or Gold-Filled Items?
These items contain only a thin layer of gold over a base metal and generally have minimal scrap value compared to solid gold. We’re happy to evaluate them, but expect a much lower offer than for solid gold pieces of similar size.
Ready to sell? See our Sell Gold page.
International Gold Purity (Fineness) Chart
| Karat | Fineness Hallmark | Pure Gold Content |
|---|---|---|
| 24k | 999 | 99.9% (pure gold) |
| 22k | 916 | 91.6% |
| 18k | 750 | 75.0% |
| 14k | 585 | 58.5% |
| 10k | 417 | 41.7% (U.S. legal minimum for “gold”) |
Many pieces, especially those made outside the U.S., are stamped with the fineness number (750, 585, etc.) instead of, or in addition to, the karat number.
Additional Testing Methods
Beyond acid, electronic, and XRF testing, a few other methods are used in the industry:
- Specific gravity testing — measures density by comparing an item’s weight in air versus water, since gold has a distinctive density that alloys and fakes typically don’t match.
- Magnet testing — a quick screening step; genuine gold is not magnetic, so an item that’s strongly attracted to a magnet is not solid gold (though this alone doesn’t confirm purity).
- Fire assay — the most precise method, used primarily by refiners, it involves melting a sample and separating the gold, this is generally not needed for routine evaluations.
Spotting Counterfeit or Misrepresented Gold
Common red flags include items stamped with a karat marking that doesn’t match their test results, unusually light weight for their apparent size, or a magnetic response. Gold-plated and gold-filled items are not counterfeit, they’re legitimately manufactured, but they’re sometimes mistakenly represented as solid gold. Our testing process catches all of these cases before we make an offer.
Frequently Asked Questions
Does gold testing damage my item?
Acid testing is done on a small, unnoticeable area, and modern electronic or XRF testing doesn’t damage the item at all.
What if my gold isn't stamped with a karat marking?
We can still test and determine the purity directly, a karat stamp isn’t required for us to evaluate your item.
Is gold-plated jewelry worth anything?
Gold-plated and gold-filled items have much less scrap value than solid gold since they contain only a thin gold layer, but we’re happy to evaluate them.
How is my final offer calculated?
We multiply the item’s weight by its confirmed purity percentage to determine pure gold content, then price that against the current market rate for gold.
Can I watch the testing process?
Yes, evaluations happen in front of you during your appointment.
Do prices change based on the day I sell?
Yes, gold is priced on a global commodity market that moves throughout each trading day, so your offer reflects current market pricing.
What does a 750 or 585 stamp mean?
These are fineness hallmarks used internationally: 750 means 75% pure gold (18k), and 585 means 58.5% pure gold (14k).
Is magnetic jewelry definitely fake gold?
Genuine gold isn’t magnetic, so a strong magnetic response means the item isn’t solid gold. This is a quick screening test, not a full purity confirmation.
What's the difference between gold-plated and gold-filled?
Gold-filled items have a thicker, mechanically bonded layer of gold over a base metal, while gold-plated items have a much thinner electroplated layer. Both have limited scrap value compared to solid gold.
What is fire assay and do you use it?
Fire assay is the most precise gold testing method, used primarily by refiners. It’s generally not necessary for routine evaluations, our acid, electronic, and XRF testing provide accurate results for standard purchases.
Can specific gravity testing be done without damaging my item?
Yes, it involves weighing the item in air and then in water, with no damage to the piece.