How To Check If Gold Is Real

Key takeaway: To check if gold is real, start with the hallmark (375, 585, 750, 916 or 999), then run the magnet test, since real gold is not magnetic, and check the weight, because gold is far heavier than the metals used in fakes. None of these home checks can prove purity. The only reliable answer comes from a professional test, and at The Gold Avenue in Illovo, Sandton every piece is weighed and read on a Niton XRF gold analyser in front of you, without a scratch, before any offer is made.

Gold gathers in drawers. An inherited chain, a single earring that lost its partner, a ring from a marriage that ended, a coin that has been in the family for years. At some point the question arrives: is this actually gold, and if it is, how much gold is in it? It is a fair question and an easy one to get wrong, because the thing most people rely on, a tiny stamp inside a ring, does not always tell the truth.

This guide covers every sensible way to check gold, from the markings stamped into the metal, to the tests you can do at your kitchen table, to the acid and X-ray methods dealers use. It also tells you plainly which tests can damage your piece and which ones prove nothing on their own. The aim is simple: understand your gold well enough that nobody can underpay you for it.

How to check if gold is real: start with the hallmark

Most gold jewellery carries a small stamp, called a hallmark, that tells you the gold content. Pure gold is soft, so it is almost always mixed with other metals to make it hard enough to wear. The carat figure tells you how much of the piece is actually gold. Look inside the band of a ring, on the clasp or tag of a chain, on the post of an earring, or on the back of a pendant. You may need a magnifying glass.

Stamp	Carat	Gold content	What it usually means
375	9ct	37.5% gold	Everyday chains, rings, bracelets and earrings
585	14ct	58.5% gold	Often seen on imported pieces
750	18ct	75% gold	Fine jewellery, engagement rings, designer pieces
916	22ct	91.6% gold	High-purity traditional jewellery and some gold coins
999	24ct	99.9% gold	Essentially pure gold: bars, some coins, very soft jewellery
GP, GF, HGE, RGP, 1/20	None	Thin layer of gold over base metal	Gold-plated, gold-filled, heavy gold electroplate or rolled gold plate. Not solid gold

So a ring marked 750 is three-quarters gold, with the rest made up of metals such as copper, silver or zinc. Those alloy metals also shape the colour. More copper gives a warmer, reddish tone. White gold is alloyed with paler metals and usually plated to get its bright finish. The carat matters because the higher the gold content, the more the piece is worth by weight, which is exactly how a buyer prices second-hand gold jewellery.

Pay special attention to the last row of that table. A stamp like GP, GF, HGE, RGP or a fraction such as 1/20 is telling you the truth in its own quiet way: the piece is a skin of gold over something cheaper. It is not a fake, but it is not solid gold either, and it will not be bought by weight.

Why a stamp alone is not proof

Here is the part many people miss. A hallmark is a useful clue, but it is not evidence on its own. There are three reasons to treat any stamp with healthy caution.

• Stamps wear away. Decades of wear can rub a hallmark down until it is faint or gone, especially on the inside of a well-worn ring or the clasp of a chain that has been worn every day.
• Stamps go missing. Plenty of genuine gold, particularly older or handmade pieces, was never clearly marked in the first place.
• Stamps can be faked. A 750 stamp can be pressed into plated or low-grade metal just as easily as into solid gold. The mark is only as honest as whoever applied it.

This is exactly why a serious buyer never prices gold on the strength of a stamp. The stamp starts the conversation. A proper test finishes it.

How to check gold at home: the magnet test

Real gold is not magnetic. Hold a reasonably strong magnet near your piece. A fridge magnet is usually too weak to tell you much. If the piece pulls towards it, there is base metal inside and it is not solid gold. This is one of the safer checks because it does not touch or mark the item.

The catch is that passing the test does not prove anything. Many non-gold metals are also non-magnetic, including the copper and brass used in a lot of costume jewellery, so a piece that ignores the magnet could still be plated or fake. Think of it as a quick way to rule something out, never a way to rule it in. There is one more wrinkle: clasps and springs on genuine gold chains are sometimes made of steel for strength, so test the body of the piece, not the clasp.

Is it real gold? The weight and density test

Gold is very dense. Pure gold weighs about 19.3 grams per cubic centimetre, which makes it far heavier for its size than most of the metals used in fakes. A solid gold chain feels surprisingly heavy in the hand compared with a plated one of the same length. That heft is one of the first things an experienced dealer notices before any instrument comes out.

The popular version of this check is dropping the piece into a glass of water to see whether it sinks quickly. Solid gold does not float or drift. In practice this tells you very little on its own, because plenty of other metals sink too.

The genuinely useful version is the specific-gravity test. You weigh the item in air, then weigh it suspended in water, and the difference lets you calculate its density. Done properly with an accurate scale, the result points to the likely purity, because each carat of gold alloy has its own typical density. It is a measured, laboratory-style method rather than a kitchen-sink guess, and it does not damage the piece. Its limits are that hollow pieces, stones and mixed metals throw the reading off, so it is best used on plain solid items and always alongside another test.

Skin, ceramic and vinegar tests, and their limits

Three more at-home tests circulate online. Each has a grain of truth, and each has a real weakness.

The skin test

You may have heard that fake gold leaves a green or black mark on the skin. Base metals like copper and nickel can do this, so a green finger after wearing a ring is a fair hint that the piece is not solid gold. The problem is that skin reactions depend on your body chemistry, your sweat, your soaps and lotions, and on the alloy metals in genuine lower-carat gold. A 9ct ring can mark some people’s skin. Treat it as a hint, not a verdict.

The ceramic scratch test

Rubbing gold across an unglazed ceramic tile is said to leave a gold streak, while fake gold leaves a black or grey one. This is broadly true, and it is the same principle jewellers use with a touchstone. The drawback is obvious: you are scraping metal off your jewellery. If the piece turns out to be gold, you have scuffed it, and if it is plated you have gone through the plating. Avoid anything that scratches, files or otherwise damages an item before it has been valued.

The vinegar test

A few drops of white vinegar on the metal is the gentlest of the acid ideas. Gold does not react to vinegar and will look the same afterwards, while some base metals darken or discolour. Vinegar is a weak acid, though, so a good plating passes easily, and it can dull the alloy in a genuine piece if left on. Wipe it off straight away with water if you try it. It rules out only the crudest fakes.

Gold-plated, gold-filled or solid gold: how to tell the difference

The hardest question at home is not “is this metal or gold” but “is this gold all the way through”. Three types of piece look identical on the surface.

• Solid gold is the same alloy from surface to core. Whatever the carat, the whole piece counts towards its gold weight. This is what a buyer pays for.
• Gold-filled (GF, often with a fraction like 1/20) has a thicker layer of gold bonded over a base-metal core. It lasts longer than plating but the gold content is small, so it is not bought by weight.
• Gold-plated (GP, HGE, RGP) has a very thin electroplated layer. It wears through at the edges and high points, which is why a plated ring often shows a different colour on the inside of the band or at the back of the shank.

Look at the places that rub: the underside of a ring, the ends of a chain, the edge of a pendant. A different colour showing through means plating. Weight helps too, because a plated piece is much lighter than a solid one of the same size. But a thick, well-made plating on a heavy brass base can fool the eye, the magnet and even a surface reading, which is why dealers cross-check with more than one method.

The acid test

The acid test is a step up from the kitchen methods and is genuinely informative, which is why jewellers have used it for generations. A small mark is scratched from the piece onto a touchstone, or a tiny notch is filed into an inconspicuous spot, and a drop of nitric acid calibrated to a particular carat is applied. If the mark holds, the gold is at least that carat. If it dissolves or changes colour, it is lower, or not gold at all. Working up through the acid strengths gives a reasonable estimate of purity.

It is reliable in trained hands, and it has one real advantage over a surface scan: filing a notch gets beneath any plating, so it can expose a plated piece that looks perfect. The drawbacks are just as real. It is destructive, because the piece is scratched or filed and the acid marks the surface. It depends on fresh acids, good light and experience. And it gives a range, not a precise reading. For these reasons it is best left to someone who tests gold every day rather than attempted at home on a piece you care about and may want to sell.

What is a gold scanner? XRF testing explained

When people search for a “gold scanner” or “gold tester”, the instrument they usually mean is an XRF analyser. XRF stands for X-ray fluorescence. The handheld device fires a low-energy X-ray at the metal, the atoms in the alloy respond with their own signature energy, and the analyser reads those signatures and reports what the metal is made of: how much gold, and how much silver, copper, zinc, nickel or anything else. The reading takes seconds and appears on a screen you can look at.

Two things make this the standard for valuation.

• It is non-destructive. Nothing is filed, marked or dissolved. A delicate antique chain can be tested without losing a single milligram, and your piece goes back to you in exactly the condition it arrived in.
• It is precise. Rather than a yes-or-no guess, you get the actual gold content of the alloy, which is the number that determines value. A piece stamped 750 that reads lower will be priced on what it actually contains, and a piece with no stamp at all will be priced on what it actually contains too.

XRF has one limit worth knowing. It reads the alloy at the surface. A thick plating over base metal can produce a gold reading from the outer layer, which is why a careful dealer combines the XRF result with weight, a look at the wear points and, where something seems off, a second method. This is also why an honest buyer tests every single item rather than sampling one and assuming the rest match.

The Gold Avenue uses Niton XRF gold analysers on every gold item it assesses, from a single earring to a bag of broken chains, and the reading is taken where you can see it. The same equipment tells the difference between a genuine gold coin and a plated copy, which is covered in more detail in how to tell if a Krugerrand is real.

Gold testing methods compared

Put side by side, the methods sort themselves into three groups: safe but weak, informative but destructive, and precise and non-destructive.

• Hallmark check. Safe. Tells you what the maker claimed. Proves nothing.
• Magnet test. Safe. Catches obvious base-metal fakes. Passing proves nothing.
• Weight and density. Safe. A good indicator on solid, plain pieces. Unreliable on hollow or stone-set items.
• Skin and vinegar tests. Mostly safe. Catch only crude fakes. Vinegar can dull an alloy if left on.
• Ceramic scratch. Damages the piece. Gives a rough yes or no.
• Nitric acid test. Damages the piece. Gives a carat range. Gets beneath plating. Needs experience.
• XRF analyser. No damage. Gives the actual alloy composition in seconds. Reads the surface, so it is paired with weight and a visual check.

The practical conclusion for a seller is short. Do the safe checks at home if you are curious. Do not do the destructive ones. Then have the piece read on an XRF analyser by a buyer who does it in front of you.

Why a proper buyer tests in front of you

There is a simple reason The Gold Avenue weighs and tests every item in front of the client: transparency removes the doubt. When you watch your gold go onto the scale and under the analyser, and you see the carat and weight on which the offer is based, you are no longer relying on trust alone. You are looking at the same numbers the buyer is.

Testing openly is also how a reputable buyer protects you from being underpaid. A worn or missing stamp does not cost you money when the metal itself is read accurately, and a faked stamp cannot inflate or deflate an offer when the true content is on the screen. If a buyer takes your gold out of sight to “check it in the back”, you have no way of knowing what was tested, or whether the piece that comes back is the one you handed over. The same thinking applies to safety: a fixed, secure premises with controlled access is a very different proposition from a counter in a passage or a stranger in a car park, and you can read how The Gold Avenue approaches this on its safety page.

Your quick checklist before selling gold

Before you take any gold piece to be valued, run through this short list. It keeps you informed and makes the visit faster.

1. Look for a hallmark (375, 585, 750, 916 or 999) and for plating marks (GP, GF, HGE, RGP, 1/20). Treat the hallmark as a clue, not proof.
2. Try the magnet test on the body of the piece to rule out an obvious fake. Remember that passing it proves nothing on its own.
3. Feel the weight and look at the wear points for a different colour showing through.
4. Do not scratch, file, vinegar-soak or acid-test a piece yourself if you intend to sell it. Damage lowers value.
5. Separate items by apparent carat and colour if you can, so each is valued correctly and nothing lower drags the batch down.
6. Insist that the buyer tests and weighs the gold in front of you and explains the offer.
7. Bring your FICA documents: a South African ID, passport or SA driver’s licence, and proof of your banking details, so you can sell on the day if you choose to.

Once you know what you have, the next question is what it is worth, and how gold jewellery is valued explains the weight-times-purity method step by step.

Frequently asked questions

Can I tell if gold is real with just a magnet?

Only partly. Real gold is not magnetic, so if your piece is pulled towards a magnet it contains base metal and is not solid gold. The problem is that many fakes and most plated items are not magnetic either, so passing the test does not confirm the gold is real. Use it to catch an obvious fake, then rely on an XRF reading for a definite answer.

Does a 750 or 916 stamp guarantee my gold is genuine?

No. A stamp such as 750 (18ct) or 916 (22ct) is a useful indicator, but stamps wear off, go missing on older pieces, and can be faked on plated metal. That is why The Gold Avenue reads the metal itself rather than pricing on the strength of a stamp. Accurate testing protects you whether your stamp is worn, absent or false.

How do you check if gold is real without damaging it?

Use the hallmark, the magnet, the weight and a close look at the wear points. Those four cost nothing and leave no mark. For a definite answer, an XRF analyser reads the alloy without scratching, filing or acid. Skip the ceramic and acid tests on anything you may sell.

What is the most accurate gold test?

For a buyer valuing jewellery, XRF analysis is the most accurate practical method because it reports the actual gold percentage of the alloy in seconds and leaves the piece untouched. Nitric acid testing is informative and gets beneath plating, but it is destructive and gives a range rather than a precise figure.

Will testing damage my jewellery?

Not at The Gold Avenue. The Niton XRF analysers used there are non-destructive, so nothing is scratched, filed or marked. Your piece is returned exactly as it arrived. This is why it is wise to avoid at-home scratch or acid tests on anything you might sell, since those leave marks that reduce the value.

How can I tell gold-plated from solid gold?

Look for a plating mark (GP, GF, HGE, RGP or a fraction like 1/20), check the rubbing points for a different colour showing through, and feel the weight, because plated pieces are much lighter than solid ones of the same size. When in doubt, an XRF reading combined with the weight settles it.

Get your gold tested and valued at The Gold Avenue in Illovo, Sandton

Having your gold checked properly does not need to be daunting. At The Gold Avenue a Purchasing Consultant weighs each piece and reads it on a Niton XRF analyser in front of you in a private, air-conditioned consultation booth. You see the weight and the purity, the offer is worked out from those figures against the live gold price with the method explained, and there is no obligation to accept. The valuation is free. If you do accept, your details are captured on an iPad, you sign a one-page Sale Agreement, and payment is made by immediate EFT or in cash, subject to ID and compliance checks and the cash available on the premises. The whole visit usually takes 10 to 15 minutes. The Gold Avenue is a registered second-hand goods dealer under the Second-Hand Goods Act and a member of the Jewellery Council of South Africa, and holds a Google rating of 5.0 from around 400 Google reviews.

Find The Gold Avenue at Office 804, 8th floor, Illovo Point, 68 Melville Road, Illovo, Sandton, 2196. Hours are Monday to Thursday 08:00 to 17:00, Friday 08:00 to 16:00, and Saturday by pre-booked appointment only. Walk-ins are welcome. To have your gold tested, call 010 109 0080, WhatsApp 076 393 5429, or book a free valuation at https://thegoldavenue.co.za/request-a-quote/.

Written by Trent Saldsman, Founder and Managing Director, The Gold Avenue.