The most reliable thing you can do at home is read the stamp. Real gold jewelry is usually marked with a karat or fineness number such as 10K, 14K, 18K, 585 or 750, with nothing after it like GP, HGE, RGP or GF. A magnet can rule out some fakes, but the popular kitchen tests (ceramic streaks, skin color, vinegar, floating) produce wrong answers often enough that they settle nothing. The only conclusive answers come from an acid test or an XRF reading at a jeweler, which takes minutes and usually costs little or nothing if you are there to sell.
Color, shine and weight in the hand are not reliable either. Brass, gold plate and solid gold look the same in a drawer and in a photo. What the stamp gives you is a starting point: a stamp of 14K with no plating letters is consistent with solid gold, and a piece consistent with solid gold is worth at least its melt value, which you can estimate with a kitchen scale.
Step one: find and read the stamp
Use a magnifying glass or your phone camera zoomed in, in daylight. Stamps hide in predictable places:
- Rings: inside the band, often opposite the stone.
- Chains: on the clasp, the tongue of the clasp or a small tag beside it.
- Bracelets: on the clasp or inside the band.
- Earrings: on the post or the clip back.
- Pendants: on the bail, the loop that holds the chain.
- Brooches: on the back near the pin.
What the numbers mean
Karat counts gold in parts out of 24. Fineness counts it in parts per thousand. They describe the same thing:
| Stamp | Gold content | Approximate melt value per gram |
|---|---|---|
| 9K or 375 | 37.5 percent | $48 |
| 10K or 417 | 41.7 percent | $54 |
| 14K or 585 | 58.3 to 58.5 percent | $75 |
| 18K or 750 | 75 percent | $97 |
| 22K or 916 | 91.6 percent | $118 |
| 24K or 999 | 99.9 percent | $129 |
These figures assume gold at roughly $4,000 per troy ounce, about $129 per gram of pure gold. Gold moves every day, so recalculate with the current spot price. A buyer will pay below these numbers, as explained further down.
A few more marks to know:
- KP after a number, as in 14KP, means karat plumb, an older American mark saying the gold meets the stated karat.
- PLAT, PT950 or PT900 mean platinum, which is denser than gold and is valued at the platinum price, not the gold price.
- 925 or STERLING on a yellow piece means gold over silver, called vermeil. It is valued as silver.
- A maker's mark next to the stamp is a good sign. Reputable makers stamped both.
Step two: check for plating marks
This is where most home checks go wrong. A stamp can contain a karat number and still mean the piece is mostly base metal:
- GP or GE: gold plated or gold electroplate, a microscopic layer.
- HGE or HGP: heavy gold electroplate, a thicker layer that is still plate.
- RGP: rolled gold plate, a thin sheet bonded to base metal.
- GF or 1/20 12K GF: gold filled, a thicker bonded layer, still mostly brass.
- 14KGP or 18KGP: plated, despite the karat number.
So "14K HGE" is not 14K gold. The plating layer is 14K, but the piece is base metal underneath and has little scrap value. Wear helps confirm this. Plated pieces often show a brassy, pink or gray color on high points and edges where the layer has worn through, while solid gold stays the same color all the way down. Our guide to old jewelry and gold stamps covers more marks in detail.
The magnet test and its limits
Gold is not magnetic. If a ring or chain jumps to a strong magnet, it is not solid gold, or at least not mostly gold. That makes the magnet a useful first filter.
It is not a proof in the other direction. Brass, copper, aluminum, many plated pieces and most fakes are also non-magnetic, so a piece that ignores the magnet could still be worthless. There are also false alarms: clasps often contain a small steel spring, so a solid gold chain can tug toward the magnet at the clasp. Test the body of the piece, not the clasp, and use a strong neodymium magnet rather than a fridge magnet.
Why the ceramic, skin and kitchen tests mislead
The ceramic streak test
The idea is to drag the piece across an unglazed ceramic tile and look at the streak: gold leaves a gold streak, fakes leave black. In practice it fails in both directions. A thick plating layer can leave a golden streak, and you scratch your jewelry doing it. It can also give a dark streak from dirt or alloy metals on a real piece.
The skin test
Green or black marks on the skin are often blamed on fake gold. Copper and silver in real 10K and 14K alloys can also discolor skin, especially with sweat, lotion or chlorine. Some cheap metals never mark skin at all. It is not a test.
Vinegar, bleach, floating and biting
Vinegar does not reliably change base metals within a few minutes, and bleach can damage real gold alloys. Gold sinks, but so does every other metal piece of jewelry, so the float test tells you nothing. Biting dates from soft high-karat coins and only leaves tooth marks on modern jewelry.
Density testing
A water displacement test can estimate density and is more scientific than the kitchen tricks. It needs an accurate scale reading to a hundredth of a gram, works poorly on small pieces, and is thrown off by stones and hollow construction. Most people get closer answers by paying a jeweler a visit.
The tests that settle it
Acid testing
A jeweler rubs the piece on a black touchstone to leave a streak, then applies acids made for each karat level. If the streak survives the 14K acid but dissolves under the 18K acid, the gold is between those purities. It is quick and cheap, but it only tests the surface, so a jeweler may file a tiny notch in an inconspicuous spot to check under heavy plating.
XRF
An X-ray fluorescence analyzer reads the metal composition in a few seconds without damaging the piece. Gold buyers, refiners and many jewelers use them. XRF also reads mostly the surface, so a thick plating can still confuse it, but it is the fastest and most accurate check you can get without melting the piece.
Electronic testers
Handheld electronic gold testers measure conductivity and are sold for home use. They are better than the kitchen tests, but readings drift with technique and plating, so treat them as a hint.
What a photo can and cannot show
A clear photo can read the stamp, the plating letters, a maker's mark, wear patterns and the style and era of the piece. That is often enough to say whether a piece is consistent with solid gold or clearly plated, and to estimate its value range.
A photo cannot measure metal content. It cannot tell an unstamped solid gold ring from a plated one, and it cannot spot a fake stamp on a well made counterfeit. The photo that helps most is a sharp close-up of the stamp in daylight with a coin beside the piece for scale, plus a shot of the edges where plating would wear through.
A melt value example
Say you have an 18K chain marked 750 that weighs 12 grams on a kitchen scale.
- 12 g x 0.75 = 9 g of pure gold
- 9 g x $129 = about $1,160 in melt value
Scrap buyers and refiners typically pay 70-90 percent of melt, so expect offers between roughly $810 and $1,045. Pawn shops often offer less. Signed pieces from fine houses and good antique jewelry can sell above melt through a dealer or an auction house, so do not scrap something with a famous signature without asking first.
Remove stones before weighing where you can, since they add weight but not gold value. And weigh in grams, not pennyweights or troy ounces, unless the buyer quotes those units.
Who to ask
- A jeweler: acid or XRF testing in minutes, often while you wait.
- A gold buyer who quotes a per gram price in front of you: get at least two quotes.
- A gemologist: if the piece has stones that may be diamonds or precious gems.
- An accredited appraiser: for insurance or estate values on fine pieces.
If your pile turns out to be mostly plated, it may still contain collectible signed costume pieces. Our guide to costume jewelry value explains which names matter.