Dec 2023


Dec 2023

How To Spot Fake Gold Coins and Avoid Fraud

By StoneX Bullion

Gold coins are a prized possession for collectors and investors alike. Whether you’ve purchased gold coins to invest in your future or crown a collection, the last thing you want to discover is that your coins are counterfeits.

Fake gold coins are designed to either replicate rare coins or make regular coins appear more valuable than they truly are. They may contain other metals or try to pass off low-quality gold as being of a higher purity grade. Fake coins can be highly sophisticated, but luckily, there are several methods you can use to discern whether or not the coins in your collection are counterfeit. Many of these tests can be done from the convenience of your own home with everyday tools and supplies.

In this guide, we share a comprehensive list of methods to test gold bullion coins so you can confirm their authenticity. Some of these methods are more reliable than others, so we recommend using a combination of tests to determine the real value of your coins.

Test your coin’s size and weight

One way to determine a gold coin’s authenticity is to test its size and weight. Gold is one of the heaviest metals on the planet and it has unique properties that are difficult to replicate. This means that counterfeit gold coins containing other metals will be larger in size than pure gold coins of equal weight.

How it works: Gold coins are usually made according to strict standards and regulations that govern their weight and dimensions. You can determine whether you have a counterfeit by checking your coin’s size and weight against the standard for its coin type.

To do it: Let’s say you have a gold Krugerrand coin and want to check if it’s authentic. Start by looking up the exact weight, diameter, and thickness of a Krugerrand like yours. For example, a 1oz Krugerrand should be 32.77mm in diameter and 2.84mm thick. Next, check the weight and dimensions of the Krugerrand in your possession. It’s likely fake if:

  • If it’s wider and thicker than the Krugerrand, or
  • It has the same dimensions but weighs less than 1oz.

The ping test

This is one of the oldest tricks for distinguishing between fake and real gold coins. All you need is your gold coin and a hard surface.

How it works: Genuine gold makes a distinctive, sharp ringing sound when it comes into contact with a hard surface.

To do it: Hold your gold coin in your hand and strike it against a hard surface or another gold coin. If it’s genuine gold, it should make a sharp, high-pitched ringing sound. If it’s made from other precious metals, the ringing sound will be much shorter and more dull than gold’s sharp ping.

Magnet test

The magnet test is another easy way to test if gold is real.

How it works: Unlike many other metals, gold is not magnetic and will not stick to magnets.

To do it: Grab a strong magnet and see if you can use it to pick up your gold coins. If your coins stick to the magnet then it’s likely that they contain a substantial amount of other metals. If they don’t stick, then it’s a good sign that your gold coins are genuine.

There’s one caveat to this test: there are other non-magnetic metals out there, such as aluminum, copper, and bronze. If your gold coins don’t stick to the magnet, there’s still a chance that they contain some of these other metals. For that reason, the magnet test is best done alongside some of the other tests in this article.

Nitric acid test

If you like taking risks, then the nitric acid test may be for you. This method is a direct way of testing gold authenticity, but if your gold coins turn out to be fake, then they can be damaged in the process.

How it works: Pure gold cannot be tarnished or dissolved by strong acids like nitric acid. If your coins are fake or mixed with other metals, they’ll corrode or change color when they come into contact with nitric acid.

To do it: You can buy nitric acid in different concentrations. The strength you want to buy will depend on the purity level of the gold coins you want to test. Start by sprinkling a drop over your gold coin. If it melts, it means that it wasn’t genuine or is mixed with lower metals. If the acid drop turns green, then your coin may be made from zinc and plated with gold. If it turns milky, then it may be a sterling silver coin plated with gold.

Magnifying glass to check for markings

This method is less of a test and more of a close, careful examination.

How it works: Examining your coins up close can help you spot clear signs of fakes, such as discoloration or particular hallmarks.

To do it: If you have a magnifying glass handy, examine your gold coin up close and check for signs of counterfeit. These may include:

  • Discoloration: Because gold doesn’t react with other chemicals, there should be no discoloration or spots.
  • Luster: Genuine gold is a soft yellow color and not very shiny. If your gold coin is too bright or shiny, or has a reddish tinge, then it may not be pure.
  • Hallmarks: Most gold coins have ‘hallmarks’ engraved on the surface. These usually indicate purity levels, weight, and mintmarks. There are also hallmarks that indicate gold plating or counterfeit coins. These include:
    • HGP: Heavy (Hard) Gold Plate
    • GF: Gold Filled
    • GP: Gold Plated
    • H.G.E: Hydrostatic Gold Electroplating.

If your gold coin contains any of the above hallmarks then it’s likely to be a counterfeit coin.

Be aware that good quality fakes can contain hallmarks that seem genuine but are false. If hallmarks seem too perfect to be true, or raise suspicion, it’s best to get a second opinion from an expert.

Scratch test

Another simple way to test for counterfeit coins is with the ceramic scratch test. This method should be practiced with caution to avoid damaging your gold coins.

To do it: For this test, you need an unglazed ceramic plate or porcelain tile. You can easily find these items online or in hardware stores.

Take your gold coin and carefully rub it against the ceramic plate or tile. Place enough pressure on it to leave a scratch but not cause any damage. If your gold coin is real, it should leave behind a golden or yellow mark or streak. If the streak left on the tile is black, then you’ve likely got a fake gold coin.

Skin test

This is one of the quickest and easiest ways to check if a gold coin is real or fake and requires no extra tools.

How it works: Unlike some other metals, pure gold doesn’t react with human skin and leave behind stains or discoloration.

To do it: All you need to do for this method is hold your gold coin in your hand for around 15 minutes. If it’s fake, it will leave behind a green or black discoloration which means your skin has reacted with other metals than gold. Be sure you don’t have any makeup or cream on your skin before conducting this test as it can lead to misleading results.

Float test

This is another simple gold testing method you can quickly do at home.

How it works: Pure gold is heavy and dense, which means it’s unlikely to float in water.

To do it: Place your gold coin in a bowl or glass of water. If it’s genuine, it will immediately sink to the bottom. If it floats or hovers, then it may be gold plated or counterfeit.

It should be noted that the float test isn’t bulletproof and should only be used alongside one of the other methods to confirm or deny results. This is because fake gold can still contain other dense, heavy metals that can sink to the bottom of a glass.

Vinegar test

Another easy way to test if gold coins are real at home is by using vinegar.

How it works: Unlike other metals like bronze, copper, or silver, gold is non-reactive and doesn't tarnish. This means that it shouldn’t change its color when it comes into contact with a substance like vinegar.

To do it: Pour a small amount of white vinegar on your gold coin. If it changes color, then it's not pure gold. If it remains the same color, then it's likely to be pure gold. You can also submerge your gold coin in a glass of vinegar for a few minutes. If it changes color after rinsing, even slightly, then it's a sign of a fake.

Makeup test

This method is slightly unconventional and even a little bit unreliable, but it can still be a good way to confirm or deny results found in other methods.

To do it: Apply a small amount of foundation to the back of your hand and sprinkle over some baby powder to help it dry quickly. Once dried, rub the gold coin over your skin. If it leaves a black mark then it’s a good sign of authentic gold.

You can also do this method in reverse. Rub your gold coin on clean skin that's dry and free from lotion or makeup. If it leaves a residue, then it may be counterfeit. If it makes no mark, then it could be real.

Know your source

One of the best ways to avoid buying fake gold coins is to do your due diligence and choose a reputable dealer or broker with a solid track record of selling pure, high quality gold coins.

Before investing in gold coins and bars, check the following:

  • Is it easy to contact the company?
  • Does the company’s representatives talk to customers first to understand their needs before selling gold products?
  • Does it feel like the representatives are pushing you to make a purchase?
  • How long has the company been operating for?
  • Are there many positive reviews online you can use as social proof?

It’s easier than ever to buy gold coins and gold bars online, which unfortunately leaves investors more susceptible to fraud and counterfeit gold. Carefully researching your source can be the best way to avoid fraud. Look out for companies that sell real gold from well-known and internationally trusted sources like the United States Mint, Austrian Mint, Australian Mint, South African Mint, or Royal Canadian Mint.

Avoid unrealistic offers

Finally, if it sounds too good to be true then it probably is. Beware of offers and prices that are below market value. If your gold coin dealer is trying to push a sale or is quick to offer discounts, then take it as a sign and look elsewhere.

Buy authentic gold coins from Stonex Bullion

Whether you’re looking to invest in gold coins for your future or to crown your collection, you’ll only find genuine coins here at StoneX Bullion. Our company has been trading since 2019 as part of StoneX Group Inc, a Fortune 500 company listed on NASDAQ.

Each coin we stock comes from the best-known mints in the world, such as the Vienna Philharmonics, Canadian Maple Leaf, and South African Krugerrand. We can assure you that the products we stock are genuine and literally worth their weight in gold.