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 try the magnet test, since real gold is not magnetic, and feel the weight, because gold is far heavier than the metals used in fakes. None of these home checks can prove purity. The reliable answer comes from a professional test, and at The Gold Avenue in Illovo, Sandton we weigh each piece and read it on a Niton XRF gold analyser in front of you, without a scratch, before making any offer.

If you have an inherited chain, a single earring or a ring you no longer wear, the first question is whether it is actually gold, and the small stamp inside it does not always tell the truth.

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, and the carat figure tells you how much of the piece is 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 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

The alloy metals shape the colour: more copper gives a warmer, reddish tone, and white gold is alloyed with paler metals and typically plated for its bright finish. The carat matters because the higher the gold content, the more the piece is worth by weight, which is how we price second-hand gold jewellery.

The last row of the table matters. A stamp like GP, GF, HGE, RGP or a fraction such as 1/20 means 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

A hallmark is a useful clue, but it is not evidence on its own. There are three reasons to treat any stamp with caution.

• Stamps wear away. Decades of wear can rub a hallmark down until it is faint or gone, especially inside a well-worn ring or on the clasp of a chain worn daily.
• 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 why we never price gold on the strength of a stamp. The stamp starts the conversation. A proper test finishes it.

The magnet test

Real gold is not magnetic. Hold a reasonably strong magnet near your piece; a fridge magnet is 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 proves nothing. 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. Use it to rule something out, never to rule it in. Clasps and springs on genuine gold chains are sometimes steel, so test the body of the piece, not the clasp.

Weight

Gold is very dense, which makes it far heavier for its size than the metals used in fakes. A solid gold chain feels surprisingly heavy in the hand compared with a plated one of the same length, and 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, but plenty of other metals sink too, so on its own this tells you very little. A dealer can measure density properly; you do not need to.

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

Fake gold is said to leave 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. Skin reactions vary from person to person, though, and a genuine 9ct ring can mark some people’s skin, so 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. 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 we cross-check with more than one method.

The acid test

The acid test is a step up from the kitchen methods and jewellers have relied on it for a long time. A small mark is scratched from the piece, or a tiny notch is filed into an inconspicuous spot, and a drop of nitric acid matched 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 filing a notch gets beneath any plating, so it can expose a plated piece that looks perfect. The drawbacks are just as real. It scratches or files the piece and the acid marks the surface. It depends on fresh acids, good light and experience. And it gives a range, not a precise reading. It is best left to someone who tests gold professionally rather than attempted at home on a piece you may want to sell.

XRF testing, the gold scanner

A gold scanner is an XRF analyser. The handheld device reads the metal and reports what the alloy 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 figure that determines value. A piece stamped 750 that reads lower is priced on what it actually contains, and a piece with no stamp at all is 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 we combine the XRF result with weight, a look at the wear points and, where something seems off, a second method.

We use Niton XRF gold analysers and test in front of you, so 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 how to tell if a Krugerrand is real.

Why we test in front of you

We weigh and test every item in front of the client for a simple reason. When you watch your gold go onto the scale and under the analyser, and you see the carat and weight the offer is based on, you are no longer relying on trust alone. You are looking at the same figures we are.

Testing openly is also how you avoid 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 we approach this on our safety page.

Your quick checklist before selling gold

Before you bring 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.
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. You do not need to, it will not change what the gold is worth, and it can spoil a piece that could be resold intact.
5. Insist that the buyer tests and weighs the gold in front of you and explains the offer.
6. 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 how an offer is worked out.

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. Many fakes and most plated items are not magnetic either, so a piece that ignores the magnet is not confirmed as gold. 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 we read 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 marks the piece and gives a range rather than a precise figure.

Will testing damage my jewellery?

Not at The Gold Avenue. Our Niton XRF analysers are non-destructive, so nothing is scratched, filed or marked, and your piece is returned exactly as it arrived. Skip at-home scratch or acid tests too: they will not change what the gold is worth, but they can spoil a piece that could be resold intact.

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. 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 and 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 by immediate EFT or cash, subject to ID, compliance and the cash available on the premises. The whole visit typically takes 10 to 15 minutes. We are a registered second-hand goods dealer under the Second-Hand Goods Act and a member of the Jewellery Council of South Africa, with a Google rating of 5.0 from around 400 Google reviews.

Find us 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, Saturday by pre-booked appointment only, Sunday and public holidays closed. 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.