How to Tell if Gold Is Fake

How to Tell if Gold Is Fake

Gold jewelry is a great investment and a thoughtful gift for almost anyone. Tasteful accessories like gold chains, watches, cufflinks, and earrings can eventually become heirlooms. However, it's important to make sure that your gold is real and not an inferior substitute. Here's some more information about the properties of gold and how you can tell if it's fake.

The Properties of Gold

a bar of gold on a pile of gold coins

Pure gold is shiny and bright yellow, and it doesn't oxidize or tarnish like copper, brass, iron, silver, or aluminum. It's soft and malleable, so many pieces of gold jewelry are alloys that also contain nickel, silver, copper, or platinum. The purity of gold is measured in carats or karats, an ancient unit of weight. Pure gold is 24 carats, and 50 percent gold is 12 carats. To get the percentage purity of gold, just divide the carat value by 24 and multiply by 100. In the United States, selling gold below 10 carats as gold jewelry is prohibited.

A variety of gold colors and alloys are available. White gold looks like silver, but it doesn't tarnish. It's often coated in rhodium to give it an especially shiny look. Gold combined with enough copper can look pink or red. Since copper is relatively hard, it's one of the most durable types of gold jewelry. This is the most durable type of gold since copper is a hard metal. Green gold or electrum often contains silver, cadmium, and zinc. However, the purity of gold is responsible for most of its value, not its color.

Gold isn't magnetic, so it shouldn't respond to even the strongest rare earth magnets. However, the clasps on your jewelry could still be magnetic. There are also many nonmagnetic metals that could look like gold.

How to Examine Gold Carefully

Use a magnifying glass to look for any signs of discoloration. This could indicate jewelry that's only gold-plated. You should also look for a purity hallmark. This can be in carats or millesimal fineness. For example, pure gold will have a small engraving that says 24K or 999. It's usually on the backs of earrings and the inner surfaces of rings. Necklaces and bracelets often have jewelry hallmarks on or near the clasp. The manufacturer's stamp is nearby. 

You should be aware of hallmarks that indicate that jewelry isn't gold. HGP means heavy or hard gold plate, and GP means gold-plated. GF is gold-filled, and H.G.E. stands for hydrostatic gold electroplating. G.E.P. means gold electroplating. Common silver hallmarks include 800, 925 and 950. 

Gold coins and bars usually have engravings with the purity of the gold, the weight, and mint marks. If you don't see a hallmark, it may have worn away over time. The jewelry could have also been made before hallmarks became common in the 1950s. Even if you see a hallmark that indicates pure gold, the jewelry could be a fake. Consider the look of the hallmark along with other factors before you decide whether jewelry is real gold.

Conduct a Scratch Test and a Skin Test

For this test, you'll need a black jeweler's stone that's specially made for gold testing, an unglazed porcelain tile, or an unglazed ceramic plate. You can buy a ceramic plate or a porcelain tile from a local hardware store. 

Scratching your gold could damage it, so you should conduct this test carefully. Rub the gold against the stone, tile, or plate firmly enough to leave a mark but not hard enough to leave a noticeable scratch on the gold. If the gold is real, the mark or streak it produces should be golden or yellow color. A black streak means you have pyrite or another form of fake gold. You can also tell if gold jewelry is fake just by wearing it. Many types of fake gold will stain or discolor your skin after about 15 minutes of contact. 

Use a Chemical Gold Testing Kit

Chemical testing kits contain acids that could harm or damage fake materials but not gold. You should only use this type of test on items that you don't mind damaging. Even if a pretty ring or bracelet doesn't contain gold, it could be valuable for its beauty and style.

Be prepared to store the acids in the kit or dispose of them safely after use. Gold testing kits contain hydrochloric or nitric acid and a dropper. You'll also need rubber gloves, a piece of glass, protective eyewear, a sharp needle, and some paper towels. Conduct testing in a well-ventilated area. Don't let the acid touch your skin, and use the glass to protect your furniture.

Nitric acid will dissolve any metal that's not gold. Putting a small amount of nitric acid on your jewelry will let you know if it's pure gold. Fake gold or an alloy will cause a reaction. Before testing, use a sharp needle to make a tiny scratch or indentation in the gold. Use the back of the jewelry if possible, and apply the acid and rinse it off as soon as possible. 

Some testing kits include different mixtures of nitric acid and other components. The acids are labeled with karat levels, and a reaction with your gold indicates that it matches the carat level or is less pure. No reaction is a sign of higher purity. Many testing kits include gold test needles so you can compare the strength of the chemical reaction with gold samples that have verified carat levels. If you need to use more than one type of acid, rinse and dry your jewelry between applications. 

Consult a Professional

Many jewelers have electronic gold testers that can measure your gold's electrical conductivity in just a few seconds. You can find out whether the item contains gold and its level of purity. Some jewelers can also test gold with sophisticated X-ray fluorescence spectrometers. These machines can send X-rays through items and then measure the energy levels of the atoms inside them. They can tell you the exact composition of your jewelry, including the percentages of gold and other metals. Contacting a professional also keeps you from damaging your jewelry by accident during testing. 

To learn more about jewelry testing and find out if your pieces are pure, contact us at Martin Busch Jewelers. We're open on weekdays from 10 a.m. to 6:30 p.m. and on Saturdays from 11 a.m. to 4 p.m.