You found a necklace at an estate sale, inherited a chain from a relative, or picked something up at a vintage market. And now you're wondering: is this actually gold?
It's a smart question. Gold-plated, gold-filled, and gold-toned pieces are everywhere, and they can look almost identical to solid gold. Knowing how to tell the difference can protect you from overpaying, undervaluing something, or missing out on a piece that's worth more than you think.
First: Solid Gold vs Gold-Plated vs Gold-Filled
Before testing anything, it helps to know what you're actually trying to distinguish between:
The tests below are designed to help you tell these apart. No single test is definitive on its own: use two or three together to build confidence.
The fastest, most reliable first step is finding and reading the hallmark — a small stamped mark that tells you the metal's purity. On necklaces and chains, this is almost always located near the clasp.
Look for numbers like these:
| Stamp | Meaning |
|---|---|
| 999 or 24K | 24-karat gold (99.9% pure) |
| 750 or 18K | 18-karat gold (75% pure) |
| 585 or 14K | 14-karat gold (58.5% pure) |
| 417 or 10K | 10-karat gold (41.7% pure) |
If you see any of those stamps, you have a strong indicator of real gold. A jeweler's loupe at 10x magnification, available cheaply online, makes reading tiny hallmarks much easier.
Watch out for misleading stamps too: GP (gold plated), GF (gold-filled), GE (gold electroplated), and RGP (rolled gold plate) all contain some gold but far less than solid gold, and their value is dramatically lower.
No stamp at all doesn't automatically mean fake. Very old pieces, handmade jewelry, and some international pieces may lack hallmarks. But it does mean you should keep investigating.
Real gold is not magnetic. In fact, gold is slightly diamagnetic, meaning it's very gently repelled by magnets.
Hold a strong magnet (a rare-earth or neodymium magnet works best, a fridge magnet is too weak) near your necklace:
Keep in mind that some non-gold metals like copper and silver are also non-magnetic, so passing the magnet test alone doesn't confirm gold. But failing it pretty clearly signals you're not looking at solid gold.
Real solid gold maintains a consistent color all the way through. There's no base metal to show through, because there isn't one.
Look closely at the areas that get the most friction and wear: around and behind the clasp, at the ends of the chain, and any surface that regularly contacts skin. If you notice silver, copper-colored, or grey tones where gold color has worn away, the piece is plated or filled, not solid gold.
On a necklace with a pendant, also check the bail — the small loop connecting the pendant to the chain. It's a structural point that gets stress and often reveals the truth about a piece faster than other areas.
This one surprises people but it works. Find an unglazed ceramic tile or plate (the rough, unfinished underside of a regular tile works). Gently drag your necklace across the surface with light pressure.
A word of caution: this test creates small scratches on the jewelry, so do it on an inconspicuous spot — ideally the clasp or a hidden section of chain. Don't use this on a piece you think might be valuable without doing other tests first.
Real gold doesn't react with skin. If you wear a gold necklace and notice green marks on your neck, that's almost always a sign of a copper base or a high-copper alloy like rose gold. Black marks can mean silver content reacting with skin acid. No marks at all is consistent with solid gold.
This one takes time since you'd need to wear the piece for a few hours, but if you've already noticed discoloration in the past, that's useful information.
Worth noting: some high-karat gold alloys with copper content, like rose gold, can leave faint greenish marks on people with particularly acidic skin. That doesn't mean the piece is fake. It's an alloy reaction, not a plating issue.
White vinegar is a mild acid that can give you a quick read on whether a piece is real gold. Apply a few drops to the metal (or briefly dip the necklace in a small bowl of white vinegar) and watch for about 15 seconds.
This is a gentler version of the acid test and won't damage genuine gold. It's not as precise as a proper acid testing kit but it's a useful quick check when you don't have other tools handy.
This is one of the most reliable at-home tests, though it requires purchasing an acid testing kit. These are available at jewelry supply stores or online for about $20 to $40 and include different acid solutions calibrated for different gold karats.
How it works: make a small scratch on an inconspicuous spot on your necklace, ideally the clasp, apply a small drop of acid, and watch:
Nitric acid testing is genuinely accurate and widely used by gold buyers and pawnshops. If you're comfortable handling small amounts of acid carefully, it's a worthwhile step before getting a professional appraisal.
The most accurate way to know for certain is a professional test. Certified gemologists and appraisers use methods that leave no room for ambiguity:
A professional evaluation also gives you something no home test can: the actual value of your piece. Gold content is only one part of it. Craftsmanship, gemstones, designer provenance, and market demand all factor into what a necklace is truly worth.
Use Unvault's Gold Calculator to estimate melt value in real time. For a complete picture that accounts for everything, submit your piece for an online jewelry appraisal from Unvault's certified experts.
Home tests narrow things down but rarely give a definitive answer on their own. A simple way to think about it:
Not necessarily. When looking at selling 14K gold or selling 10K gold, it is important to note that they can develop a slight tarnish over time due to their alloy metal content. Tarnish on the surface doesn't change the gold underneath.
If a necklace looks a bit discolored but has genuine hallmarks and passes the magnet test, it may just need a good cleaning.
Ready to Find Out What Your Gold Is Worth?
Once you've confirmed the necklace is real gold, the natural next question is what it's actually worth. Use the Gold Calculator for a quick estimate based on weight and karat. Get a full online jewelry appraisal for a comprehensive valuation. Or if you're ready to sell, explore options to selling 14K gold or sell 18k gold with Unvault.
Here's a quick recap of all 8 tests:
| Test | Reliability | Cost | Time |
|---|---|---|---|
| Check hallmarks | High | Free | 2 min |
| Magnet test | Moderate | ~$10 for magnet | 1 min |
| Look for wear-through | Moderate | Free | 5 min |
| Ceramic streak test | Moderate-High | Free | 2 min |
| Skin discoloration | Low to Moderate | Free | Few hours |
| Vinegar test | Moderate | Free | 5 min |
| Acid test | High | $20 to $40 kit | 10 min |
| Professional XRF | Definitive | $25 to $75 | 30 to 60 min |
No single home test is conclusive on its own. Use two or three together to build confidence, and when real money is on the line, get a professional assessment.
Last updated: June 2026. Gold hallmarking standards vary by country. If you have a piece from an unfamiliar region, a local appraiser is worth consulting.
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