Guilherme Radaeli is a lawyer, writer and blogger born in the state of São Paulo, Brazil. Part-time techie and overall mad lad.
All That Glitters Is Not Gold
Gold has always been special to the human race, because of its beautiful metallic yellow hue, its resistance to corrosion, its eternal luster and its strange malleability. In modern civilization, gold has many different applications in chemistry, electronics and industry.
Another reason gold is important is its rarity. Having an atomic number of 79, it's one of the rarest elements that occur naturally in the universe. As such, it's not surprising that, throughout the ages, many dishonest people have attempted, with varying success, to replicate gold's qualities using more common elements, in order to trick prospective gold traders and gain an unfair economic advantage.
The jewelry trade is one in which these practices are most highly developed, since most people interested in buying jewelry are not well informed about gold's physical and chemical qualities.
However, there are many easy ways to test if your expensive jewelry is made from actual gold, and this article will show you some practical tests that can be used by any layman.
1. The Smell Test: Ideal for Small Gold Pieces
While this test is far from being the most reliable way to tell real gold from fake gold, it's one of the easiest and quickest to do, and will not damage your jewelry.
You know that awful smell your hands get after you hold some coins in it for some time? We're looking for that smell in this test.
This test can be done in three easy steps:
- Make sure your hands are sweaty (not dripping with sweat, but slightly sweaty), then place your gold jewelry of choice in the palm of your hand
- Place your other hand over it, and vigorously rub your hands together with your jewelry between them;
- Finally, place your nose close to your palms and smell them. If it does not smell like anything in particular, then your jewelry has passed the test. But if your hands smell like coins, then it's quite likely you're dealing with fake gold.
You see, one cheap metal used in the making of coinage (and fake gold jewelry) is brass, a mixture of copper and zinc along with other materials. Brass can look like gold, especially if made into an alloy with other metal, to try to approximate gold's weight and color. However, brass is much more reactive than gold; when in contact with salty water (like sweat) and air, it produces the characteristic acidic smell most coins have, due to an electrolytic reaction.
As such, if your "gold" jewelry exhibits the same smell, it very likely is not real gold, or at least not pure gold. But even if your gold jewelry passes this test, it can still be fake gold.
2. The Magnet Test: Use a Powerful Neodymium Magnet
For this test, you'll need a rare earth magnet.
Rare earth magnets aren't the common type of magnets you can find on your fridge, for example. They are made of special alloys which give them incredible power. For this test, a neodymium magnet is recommended, as they are readily available online, very affordable, and among the most powerful rare earth magnets.
Now, to test your jewelry, simply touch it with the magnet. Pure gold will not be attracted to the magnet. If the jewelry gets attracted to the magnet (even if just a little), then at least part of it is not gold. Gold chains and collars commonly have a "clasp" mechanism of some sort, and you may find that only the clasp bit sticks to the magnet. This is because there is a spring inside the clasp mechanism, and gold doesn't make good springs.
Remember, however, that even if your jewelry piece does not get attracted to the magnet, there's still a chance it may not be gold. This is because other, non-magnetic elements can be used in making fake gold. Most commonly, though, fake gold is composed using metals that are at least somewhat magnetic, and a strong rare earth magnet should be able to exert some attraction over these.
3. The Fire Test: Burning to Test Jewelry
This is an easy-to-do test commonly known by pawnshop owners, who often are presented with gold jewelry that could be fake. It's quite easy to do in these easy steps:
- First, make sure you have a lighter that produces a constant flame that's not very small. An ordinary disposable lighter is not ideal, but can be used. Also, make sure your lighter is properly fueled with lighter fluid and not some other kind of fuel.
- Now, hang your jewelry on a piece of metal or some other tool that won't melt or burn. You can also carefully hold it using pliers. You might want to cover the ends of your pliers with tape, to minimize the risk of damaging your jewelry.
- Finally, proceed to apply the lighter's flame to your gold piece. Keep the flame on it for about a minute. If the metal starts to get darker and darker, chances are it's not gold.
Real, pure gold, when exposed to the flame, will get brighter after a while as it gets hotter, but will not darken. Fake gold pieces, such as fool's gold (actually pyrite, an iron sulfide) and pieces made of brass, iron or copper alloys will darken or otherwise change color when exposed to fire. Additionally, if the jewelry piece is only gold plated (covered with a thin layer of gold, but made of other metals inside) then the thin gold plating should start to melt, revealing the inner metal.
If your gold item has a gold content less than 18k, the results may not be consistent. If you want to be certain, consult a professional.
4. The Density Test: Use Water to Test Density
This is a decent way to tell if your gold jewelry is real without any risk of damaging it, but it requires a few tools and some knowledge of math.
- First, you need to find out the weight of your piece in grams. This requires a small, sensitive scale. but you can ask a jeweler to do it for you.
- Secondly, you'll need to fill a vial with water. Make sure the vial is big enough to hold your gold piece in it. Do not fill it to the top, but fill it just enough so that you can completely submerge your gold piece in the water. It also helps if said vial also comes with measuring lines on it. Measuring vials can be bought in any lab supplies store;
- Now you want to place your gold piece in the vial with water. Take note of the difference in water level from before and after you put the gold piece in and calculate the difference between the two measurements (just subtract the smaller measure from the greater measure);
- Now, here comes the math part. Use the following formula to calculate the density of your gold piece: Density = mass/volume displaced. A value close to 19 g/ml indicates that your jewelry piece is either gold or a material with a density that is close to gold's.
Gold pieces of different purity have different density ratios. Use these values as guidelines to find out:
12.9 to 14.6 g/ml
18k yellow gold
15.2 to 15.9 g/ml
18k white gold
14.7 to 16.9 g/ml
17.7 to 17.8 g/ml
Even so, expert craftsmen may be able to create material that looks like gold and has similar density, so make sure to test your gold using other methods as well.
5. The Ceramic Test: Unglazed Ceramic Tile
This test is actually quite simple and takes only a second to do. To do it, you'll need an unglazed piece of ceramic, such as the unglazed bottom of a plate. If the ceramic is glazed, this method will not work.
To do this, simply pick your gold piece and carefully drag it across the unglazed ceramic surface, so that it creates a streak on it. A black or otherwise dark-colored streak means your piece is not made of gold, while a gold streak indicates that it is genuine.
Again, be careful when doing this, and bear in mind that your item may end up scratched. Usually, a little polish is enough to do away with the marks, but if done improperly, the piece may require repair. Always use common sense when conducting these tests.
Another Word of Caution
This article only lists five of the easiest methods to test your gold. As said before, a skilled craftsman may be able to replicate most qualities of real gold using other elements, so even if your piece passes a few of these tests, it's always good to conduct others, just to make sure. The more tests it passes, the more likely it is to be genuine gold.
There are other ways to test your gold, but these usually require special materials (such as nitric acid) or special tools.
And finally, remember, however, that it is always better to have a professional test your gold piece.
Here are some tests you can try at home to see if silver jewelry is fake.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2015 Guilherme Radaeli
Richard little on June 20, 2020:
If gold has been though a house fire it does change the color.
SHIFTYWILSON 789 on April 29, 2019:
lonnie gollaher on September 30, 2016:
When you test 9k gold does it fizz and leave a blueish green mark
Guilherme Radaeli (author) from São Paulo - Brazil on June 17, 2016:
Thanks a lot guys! There are other methods of testing gold, but I didn't include them on this hub because they require special materials and are not the kind of thing you can usualy do at home.
Dr Vinod Saksena on April 30, 2016:
Thanks a lot for this very informative post. I have learnt something about checking the purity of gold jewellery my wife, Renu, has in her possession and for the items she might like to buy in future. Although I do not claim to suddenly have become an expert , but, may be perhaps a bit wiser ! Thanks again.
Nikki on July 24, 2015:
I love your post, great idea's, although i knew 4 out of 5 of the tests, if you have any more knowledge i would love to read and learn all i can about the subject. Me and my husband always go to thrift stores and places of such and have gotten pretty lucky only due to others not knowing much about the different stamps it carries. Most people only look for the type of stamps of purity in the kind it is, (10k,14k etc.) Thank you for sharing and again if you know of other ways of testing while someone is looking in such stores and short quick tests can be done, i would love to read them. Thank you and good luck to you.