Suppose you are a gold bullion investor, coin collector, or someone who enjoys jewelry or precious metals in general. In that case, you might have already wondered if gold, the most desired precious metal in the world for millennia, is attracted to a magnet.
In fact, you might have even heard that it is possible to figure out if a gold piece is actually false by using a magnet.
In this article, we will break down scientifically how a magnetic field works and if pure gold, like silver, is a non-magnetic metal as well.
How Does a Magnet Work?
Magnetism can be defined as a physical force between the electric charges from two different materials. That force can be either attractive or repulsive. But to understand how it works, we must delve deeper into the matter (pun intended).
Every material, substance, liquid, object, or even the air, is composed of atoms, consisting of mainly three different particles: protons, neutrons, and electrons. The protons and neutrons are the core of the atom, its nucleus. Surrounding that center, always spinning, are the electrons.
Different elements have different numbers of electrons. In the ones that have an even number of that electric particle, such as cloth or wood, the electrons spin in opposite directions. That negates any magnetism. On the other hand, in materials that have an odd number of electrons, these particles spin in the same direction. When an unpaired electron from one material aligns with an unpaired electron from another, that pulls them together.
Conversely, in other materials where all electrons are paired, the realignment of the electrons when they come within range of a magnetic field forms a negative susceptibility. In other terms, these materials actually push away from a magnet.
Most elements of the universe can get classified as diamagnetic, paramagnetic or ferromagnetic.
Diamagnetic materials such as pure gold and silver have a weak, negative susceptibility to magnetic fields. Diamagnetic elements like pure silver get slightly repelled by magnetic fields, and the content does not retain the magnetic properties when the external field gets taken away. In diamagnetic materials, all electrons are paired, so there is no net magnetic field or force per atom within. Diamagnetism arises from the realignment of the electron paths under the influence of external magnetic fields. Most periodic table elements, including copper and silver, are classified as diamagnetic.
Paramagnetic materials have small, positive susceptibility to magnetic fields (having a slight attraction to magnets). Although a magnetic field slightly attracts these materials, the content does not retain the magnetic properties when the external magnetic field gets removed, meaning it cannot become a permanent magnet. Paramagnetic properties result from some unpaired electrons and the realignment of the electron paths caused by the external magnetic field. Paramagnetic materials include palladium, platinum, rhodium, rhenium, ruthenium, magnesium, molybdenum, lithium, and tantalum.
Ferromagnetic materials have significant, positive susceptibilities to external magnetic fields. They show a strong attraction to magnetic fields and can retain magnetic properties after the external magnetic field has gotten removed. Ferromagnetic materials have some unpaired electrons, so their atoms have a net magnetic attraction. They get their strong magnetic properties due to the presence of magnetic domains. When a magnetizing force is applied, the areas become aligned to produce a strong magnetic field within the part. Iron, nickel, and cobalt are examples of ferromagnetic materials.
Non-magnetic metals are the ones that do not retain ferromagnetic or paramagnetic characteristics. Most common metals we can find daily, such as aluminum, lead, copper, brass, silver, tungsten, and titanium, are not magnetic metals. They cannot be made into magnets and will not be attracted to magnetic fields.
Is Gold Magnetic?
Gold is a diamagnetic metal, which means it is not attracted to a magnet. In fact, it has a slightly repellent property against magnets.
Gold atoms have an odd number of electrons (79), which means they will always contain one unpaired electron. Nevertheless, due to its extreme density, those electrons bond with each other and cannot be aligned to an unpaired one from a magnetic material.
Gold has an atomic weight of 196.96657 u and a density of 19.3 g/cm³, being one of the densest metals there is. It is also the explanation for other of gold's unique properties, i.e. its high melting point, low reactivity, and electrical conductivity.
You can see how gold reacts to a magnet for yourself in the following video:
Is Gold Jewelry Magnetic?
As we have mentioned above, pure gold is not magnetic. Therefore, 24-karat gold jewelry will not be attracted to magnets.
On the other hand, gold alloys that contain iron, cobalt, or nickel can be magnetic. It is not the gold that is creating magnetism. The magnet attracts the other magnetic metal mixed in the composition, i.e. iron or nickel.
Therefore, 18k, 14k, or 10k gold could be magnetic if they are alloyed with a magnetic metal.
Why Do Jewelers Add Other Metals to Gold?
There are two main reasons why jewelers mix other metals with gold: first, gold is a malleable metal. It is a soft metal. So, to make the gold piece harder and more durable, jewelers will add other metals to the alloy.
The second reason is that it makes the gold piece cheaper. You can expect 24k gold jewelry to be marginally more expensive than a 14k one.
One of the possible downsides of mixing other metals into a gold alloy is that the piece can trigger skin allergies. Copper, iron, nickel, and zinc are some examples of metals that can cause some sort of dermatitis if in contact with the human skin for too long if the person is allergic to such materials.
Gold-Plated vs. Real Gold
Gold plating is a method of covering the surface of another metal, such as copper or silver, with a thin layer of gold. Although very common in the jewelry industry, a gold-plated piece is not considered real gold.
Many will argue that for a piece to be considered "real gold," it must be at least 10 karats (or 41.7% pure gold).
Magnetism as a Test for Gold
The most trusted method of testing your gold pieces, such as gold coins or gold jewelry, is to take it to a reputable gold dealer. However, it is possible to do a magnet test to check if your gold piece is 100% pure or possibly, fake gold.
As aforementioned, 24k gold is not magnetic. If your gold piece is attracted to a magnet, you might not be able to ascertain its exact purity levels, but you could, most likely, discard the possibility of it being 100% pure.
You can watch the following video and read our article on how to tell if gold is real to learn more about possible tests you can take. Discover chemical tests and the proper electrical equipment that would give you a more accurate result.
Why Can a Metal Detector Find Gold?
Metal detectors transmit an electromagnetic field into the ground. If the wave meets a metal object, it becomes energized and retransmits an electromagnetic field too. The metal detector search coil can receive the retransmitted signal and inform the user.
However, metal detectors should be set to operate at the correct frequency to be able to detect small gold pieces. For instance, a metal detector operating at 5kHz will easily find high conductors such as large silver but will have difficulty detecting small gold ores.
Conversely, if the metal detector operates at 40kHz, it will be easier to find small gold, like a gold coin, and harder to find large silver. The same can be true for other materials or other precious metals.
Can Gold Stick to a Magnet?
Gold cannot stick to a magnet and, in fact, it will slightly repel it. Gold is a noble and precious metal along with silver, and has many properties. Gold is ductile, malleable, reflectible, and an excellent conductor of energy and heat. But not magnetic. If in contact with a magnet, your golden piece sticks to it, it may indicate that it is not pure. It is probably an alloy with another metal, which may be magnetic.
Can You Make Gold Magnetic?
Pure gold is not magnetic. So an item made of pure gold itself will not stick to magnets. A possible option to make gold magnetic is to alloy it with another metal, like iron or nickel. As they are magnetic, the alloy would promote magnetism. Some recent research discovered that applying heat to gold would make it magnetic, but only under specific conditions.
Is 24k gold magnetic?
24k gold is not magnetic. Karatage is a metric system expressed in 24 parts, used to say the levels of gold in a particular alloy. 24k indicates that all the 24 parts of an alloy present levels of gold higher than 99.95%. In other words, the analyzed gold is pure, and no other metals are mixed. If pure gold is non magnetic metal, consequently, neither is 24k gold.
Does 18k gold stick to a magnet?
It is possible that an 18k gold piece sticks to a magnet. 18k or 18 karat means that a specific alloy contains 75% of pure gold and 25% other metals. Since pure gold is not magnetic, gold itself will not be responsible for the magnetism, but the metal alloyed may be. 18k gold is usually proper to manufacture wearable jewelry, alloyed with nickel, silver, or copper, which make the pieces stronger, as gold is too malleable.
Does a magnet stick to 14k gold?
Gold, in its pure form, does not promote magnetism. If a specific item containing gold sticks to a magnet, it is possible that the metal alloyed with gold is magnetic and causing the attraction. 14k indicates that the alloy has approximately 58.3% of gold, which is low compared to 18k or 24k, and the rest of the composition consists of another metal, which may be magnetic.
What does it mean when gold is magnetic?
A magnet does not attract gold. If a particular item containing gold, such as gold coins, gold rings or necklaces, sticks to a magnet, it is probably not composed of gold only. It may be the result of an alloy of gold and another metal. Gold jewelry, for example, is usually a combination of gold and other metals to gain some resistance.
How accurate is the magnet test for gold?
Magnet testing may fail if the metal alloyed with gold is not magnetic. Then, the magnet would do a false reading. Specific thermo or electronic testing machines are proper to make this test and provide reliable results. Professional evaluators tend to use this technology to analyze gold levels of purity accurately.