Gold is valuable, so imitations sold as a “real gold” are not uncommon. By most standards, anything with less than 41.7%, or ten karats of gold would be called a blend or given some other name. If you came across a piece of jewelry of an uncertain origin or are just curious whether your gold is real or fake, you can start with inspecting the gold and testing its properties.
Please note: some of these gold testing methods can damage the jewelry. We will make sure to let you know upfront: do not try those on the gold which does not belong to you, or if it is a piece you do not want to damage.
The Gold Hallmark Test
A hallmark is a tiny stamp on the piece of jewelry with the letters and numbers code that can tell you what it is you are purchasing. In most countries, jewelers are required to put the authenticity and the karate code on every piece they produce.
However, older pieces of jewelry may lack visible hallmarks. Hallmarking became common in1950s. But, for example, in India, it only became a legal requirement in 2000. And some pieces of old jewelry could initially have a hallmark, but it was worn off: this is more common for rings with the stamp on the inside. There are other tests to help in those cases.
Why Is It Important To Know Karats?
Karats tell you the percent of gold in the blend. Most jewelry would not be made of pure gold, which is marked as 999 (99.9% pure gold) in Europe and 24K in the US. That is because pure gold is not only expensive but also very soft. That jewelry can deform and get scratched easier.
The smaller the karat number, the more there are other metals mixed with the gold in the jewelry, the cheaper it is. For example, 10K means it contains 10 of 24 karats of gold: less than half of the mix (10/24).
Sometimes, there are also letters, for example, GP, GF, and GEP. These codes mean that the item is gold plated: there is a thin layer of gold on top of some other metal. It is significantly less valuable.
The Nitric Acid Test
Acid is dangerous! Do not forget to put on latex gloves and work in a well-ventilated room to avoid any issues with this dangerous acid. You can get a special acid kit to test gold at home, but this method is best conducted in a safe environment by trained professionals. It is also recommended mainly for scrap jewelry, not gold jewelry you intend on wearing because it requires a scratch on your item. If it is a valuable piece, take it to a professional jeweler instead of doing the test yourself.
Make a tiny scratch on your piece of gold and dig it a little with a sharp tool to expose the fresh layer or the underlying metal. Drop a tiny amount of liquid nitric acid on that scratch and wait for a chemical reaction. Pure gold will not react to the acid and will not change the color. If it produces green color, it is anything but pure gold. Gold-over-sterling silver will become milky in appearance. If the acid turns gold-ish, you have gold-plated brass.
The Magnet Test
The magnetic test is the most convenient, safe, and portable test for genuine gold. Genuine gold is not magnetic: the magnet will not pull it. Imitation gold and other alloys will attract the magnet. Kitchen magnets that we put on the fridge will not do; they can be too weak to pull anything. A neodymium magnet would work much better. The magnet test is not entirely fool-proof: fake gold can be made with stainless steel, which is also not magnetic. And some gold items might have iron parts for the decorative purposes.
The Float Test
The Float Test is the simplest and safest test: all you need is a cup of water. Real gold is very heavy, so it will immediately drop down to the very bottom. If the item sinks slowly, hovers or floats over the bottom, that is not gold. Pieces with some inclusions such as amber or precious wood might not stand the test. You can leave your piece wet for some time: pure gold will not rust or change color.
The Unglazed Ceramic Test
This test scratches the gold a little but usually does not leave as much noticeable damage as the Acid Test. Find a tile or plate made of unglazed ceramic. Drag your item across the ceramic until you see the gold leaving a streak on the surface. If it is black, the gold is not real. A gold stripe usually indicates authentic gold.
If these tests did not help you to get enough proof and you are up for some more scientific experiments, we prepared another article with the Density Test explained in detail.
About the Author
Antonia is a sociologist and an anglicist by education, but a writer and a behavior enthusiast by inclination. If she's not writing, editing or reading, you can usually find her snuggling with her huge dog or being obsessed with a new true-crime podcast. She also has a (questionably) healthy appreciation for avocados and Seinfeld.
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