Is Gold Magnetic? The Physics of Diamagnetism and the Magnet Test

Is gold magnetic? No. Pure gold is diamagnetic, which means it is very weakly repelled by a magnet, so weakly that a household magnet shows no effect at all. If you are in Miami and wondering whether a fridge magnet can test a gold chain or ring, the answer is that it can catch some fakes but it can never prove that something is real gold.

Three kinds of magnetism, simply explained

Every material responds to a magnetic field in some way. Scientists group the responses into three main families:

• Ferromagnetic materials, such as iron, nickel and cobalt, are strongly attracted to magnets and can become magnets themselves.
• Paramagnetic materials, such as aluminum and platinum, are weakly attracted.
• Diamagnetic materials, such as gold, silver, copper, water and diamond, are weakly repelled.

Only the first group produces the satisfying snap you feel when a magnet grabs a paper clip. The other two effects are real but tiny at everyday field strengths.

Why is gold diamagnetic?

Ferromagnetism comes from unpaired electron spins that line up together in regions called domains, so their tiny magnetic moments add up. Gold does not have that arrangement.

Diamagnetism, on the other hand, exists in every material. When a magnetic field is applied, the motion of electrons around their atoms adjusts slightly and creates a small opposing field, a consequence of Lenz's law. In metallic gold, that opposing response from its many tightly bound inner electrons outweighs any weak attraction, so the net effect is a gentle push away.

That is why the Wavy Diamond Hoop Earrings, in 18K recycled gold with natural diamonds, will simply ignore a magnet. Both the gold and the diamonds are diamagnetic.

Can diamagnetism ever be seen?

Yes, with a very strong magnet. In 1997, scientist Andre Geim and colleagues at Radboud University Nijmegen levitated a living frog inside a powerful magnet, using the diamagnetism of the water in its body. The experiment later won an Ig Nobel Prize, and Geim went on to share the 2010 Nobel Prize in Physics for work on graphene. Pyrolytic graphite, a form of carbon, is diamagnetic enough to float above strong rare earth magnets on a desk. Gold's diamagnetism is weaker, so you will not see a gold ring float.

What about 14K and 18K gold?

Karat gold is an alloy. 18K gold is 75 percent gold and 14K gold is 58.5 percent gold, with the rest made of metals such as silver, copper and zinc, which are also not ferromagnetic. Our guide to karat stamps and hallmarks explains what 585 and 750 mean.

So a solid gold piece should not stick to a magnet. If a whole chain jumps toward a magnet, the core is likely a ferromagnetic metal such as steel or iron under a thin gold layer. That is one of the clearest differences between solid gold and plated pieces, covered in our science of gold layers.

Raw textured pieces like the Dana Raw Heart Ring, cast gold around a natural heart shaped diamond, follow the same physics: no pull, no snap.

Why the magnet test cannot prove gold

• Many fakes are not magnetic either. Brass and copper, common bases for imitation jewelry, are not attracted to magnets.
• Clasps can fool you. The spring inside a clasp is often steel, so a real gold chain may twitch near a magnet at the clasp only.
• It says nothing about karat. A magnet cannot tell 10K from 18K.

Jewelers and assay offices use better tools: hallmarks, X-ray fluorescence analyzers that read a metal's composition, acid testing and density measurements. If you want to understand the density method, read why gold is so heavy.

A surprising twist: magnets and lab grown diamonds

Natural diamond is diamagnetic. But some lab grown diamonds made by the HPHT method, high pressure and high temperature, can contain tiny inclusions of the metal flux used during growth, often iron, nickel or cobalt. GIA has noted that some HPHT synthetic diamonds can be attracted to a strong magnet for this reason. It is a clue, not a final test, and gemologists rely on spectroscopy and imaging to be sure. Our article on CVD vs HPHT lab grown diamonds explains how they are made.

The Sahara Oval Diamond Ring holds an approximately 1 ct GIA certified natural oval diamond, set in 18K recycled gold with raw desert texture. Margaret Krinetz Fine Jewelry, handmade in Tel Aviv and shipped to Miami, makes every piece to order.

Frequently asked questions

Will real gold stick to a magnet?
No. Solid gold is diamagnetic. A strong pull usually means a ferromagnetic metal is present, often in the core or the clasp.

Is the magnet test enough to buy safely?
No. Use it only as a first filter. Look for hallmarks and buy from a jeweler who states the metal and karat clearly.

How long does delivery to Miami take?
Each piece is made to order in 4 to 6 weeks, then shipped by DHL Express in 3 to 5 business days. Shipping is free on orders over $1,500.

Have you ever tried the magnet test on your own jewelry? Tell me what happened, I would love to hear.