For low oxidation ability, gold is classified as a noble metal. Hence its value. At the same time, gold is a soft metal, so products made of pure material are very fragile. To increase the resistance of jewelry to gold, silver and copper are usually added. In some countries, it can be zinc, nickel, palladium and cobalt. These metals increase the strength of the product, but they must be in small doses, because it is gold that provides the product with resistance to corrosion.
Why brand gold
To show the proportion of gold in the product, they put a mark on it, which is also called a breakdown. In countries with a metric system, the sample is expressed in the number of grams of precious metal per kilogram of alloy. For example, a 585 sample means that 585 grams of gold are present in a kilogram of this alloy. In other words, this product is 58.5% precious metal.
In countries with a non-metric system, carats are used in the product to indicate the ratio of noble and other metals. In some countries, both metric and karat samples are allowed. At the same time, exclusively gold is measured in carats; metric tests are used for other noble metals.
If you do not know how to check gold for authenticity at home, first of all carefully examine it for external damage and the presence of official signs.
If you find a carat mark, you should be aware that:
- 9 carats corresponds to 375 samples.
- 12 carats - 500 samples.
- 14 carats - 585 samples.
- 18 carats - 750 samples.
- 21 carats - 875 samples.
- 22 carats - 917 samples.
- 23 carats - 958 samples.
- 24 carats - 999 samples, and denotes a noble metal in its purest form.
A gold product should not have obvious signs of corrosion. If there are any, this means that the product contains no gold or its specific gravity is below 30%.
How to check gold iodine
If during the examination of the product you did not find its sample, then iodine will help you find out whether it is gold or not. Since iodine is one of the few substances that nevertheless react with gold, it will help in the best way possible to determine its authenticity.
To detect the presence of gold in the alloy, you need to apply a little iodine on it. After a minute, iodine can be washed. A stain should remain on the product. If it is not, it is not of gold. If the product turned out to be genuine, its sample can be determined by a jeweler or using special equipment. Such a service is likely to be not free.
How to check gold with iodine, so as not to damage the product? You must act with extreme caution. It is best to apply iodine from the wrong side. The spot that appears should be immediately erased with a Coca-Cola drink or toothpaste.
If there is no iodine in the house, ordinary vinegar is suitable for checking. Dip the product in a container of vinegar, and if the product is dark, there is no gold in front of you.
Magnet Gold Check
Gold does not have the ability to magnetize, as well as metals, which are usually found in jewelry alloys. Therefore, this method is not so much for determining the presence of gold as its absence. You need to take a magnet and bring it closer to the product. If the product sticks to the magnet, it is definitely fake. The method is good if you are trying to bluff openly. After all, with the growth of modern technology, you can fake jewelry even at home.
Check with a pencil
How to check gold at home with silver nitrate or, simply put, a lapis pencil? This pencil is the result of the reaction of silver and nitric acid. It is an excellent reagent and is widely used in medicine for sterilizing wounds. We will need it for an experiment with gold. Since silver nitrate is readily soluble in water, it is worth wetting to speed up the reaction. Then draw on it with a lapis pencil. There should not be any marks on the gold product.
Tooth Gold Check
How to check gold if there are no available means? You probably could see in films how pirates who find gold try it on the tooth. Olympic champions do the same when presenting them with gold medals, which has become a tradition rather than a real test. In fact, this ancient as the world method operates to this day. Since gold is a very soft metal, after a bite of not even pure metal, a trace should remain on it. And the deeper it is, the more gold in the product, and, accordingly, the higher its fineness.
Density Authentication
Gold is a very heavy metal. Its density is 19.32 g / cm 3 , second only to six other equally rare metals. Therefore, this quality is often used to determine the authenticity of gold. For example:
- 14 carats (583 samples) corresponds to a product density of 12.9 - 14.6 g / cm 3
- 18 carats (750 samples) corresponds to a product density of 15.2 - 15.9 g / cm 3
- 22 carats (916 samples) corresponds to a product density of 17.7 - 17.8 g / cm 3
- 24 carats (999 samples) corresponds to a product density of 19.32 g / cm 3
To begin with, weigh your product. If you do not have special weights, you can do this at a pawnshop. Unlike specimen definition, jewelers provide this service for free.
Then take a test tube, preferably with a graduated scale, and fill it with water. The amount of water does not matter. The main thing is that it covers the product. Dip the jewelry into the tube and see how much water has risen on the scale. So you know the volume of the product.
Dividing the weight of the product by its volume, you will get its density.
For example, take gold 585. How to check? After weighing, we learned that the product weighs 27 g. Having lowered the product into the water, we saw that the water rose by 2 ml. So, the volume of the product is 2 cm 3 . Dividing the weight of 27 g into a volume of 2 cm 3 , we obtain a density of 13.5 g / cm 3 , which corresponds to 14 carats.
How to test gold using ceramics
And if you don’t want to bite dubious products, and besides, there is no necessary equipment in the house? How to check gold at home in this case? The answer is simple - with ceramic dishes. Take a plate, preferably white, and which will not be a pity to spoil. Put the product in it and rub a little. If there is a black trace on the plate, then the product is not made of gold, but if the trace is yellow, then most likely the product is genuine.
Knowing how to check gold, you can not only protect yourself from scammers, but also easily and quickly determine the value of jewelry found.