American jewellers consider gold a metal that is more than 10 carats. If you are not sure in quality and originality of gold jewellery, the best way to testify it is to show to certified professionals. But if you want to check your jewellery with no time lost, there exist 6 easy tests you can carry out even at home.
Method 1: Identification by eye
It is the first and the easiest way to testify if the gold is real. Check the particular signs, all gold items have. Look for official marks, check karats or fineness with the help of looking glass. You may not find marks at old jewellery because of wearing. It often happens that forgery has the same marking as real gold; sometimes professional testing is needed anyway. Also check a color, especially in places that fall for permanent attrition; usually it’s the edges of the item. If the gold fades to another metal, it’s probably jewellery that has just a plating of gold.
Method 2: Bite test
Do you remember Olympic Games winners biting their medals? Do you thing they check if the gold is real? Try the same method; moderately bite the jewellery and look for the traces.
If the gold is real, you will notice marks and if you see deep traces from your teeth, it is probably pure gold. But we don’t recommend you to conduct this test as it can lead to serious damage of the teeth.
Method 3: Magnet test
It’s easy to conduct, but not very authentic. Take a strong magnet (travelling magnets from your fridge will be too weak), which you can find in specialized stores or in kid’s toy or woman’s purse clasp; and hold it near jewellery. If the magnet sticks the item, it is fake gold. Real gold is non-magnetic metal, so it will not react with magnet. But sometimes forgeries also contain such metal, so don’t rely on this test entirely, try others as well.
Method 4: Density test
Gold with its density about 19.3 g/ml is one of the most solid metals. Pure gold has the highest density. This test fits only for jewellery without gemstones. Attentively read instructions bellow before conducting it.
Weigh the jewellery, usually you can find this information at the label. Then take a flask (better with millimeter marks) and fill it with water. Put your jewellery in the flask and accurately measure the amount of water before and after immersion of the item. Cipher out the difference and use the next formula. Mass/volume displacement = density. If the result is near 19 g/ml, it might be real gold or metal similar to it.
This information will prompt you which g/ml ratios contain gold with different purity:
14K – 12.9 to 14.6 g/ml
18K white – 14.7 to 16.9 g/ml
18K yellow – 15.2 to 15.9 g/ml
22K – 17.7 to 17.8 g/ml
Method 5: Ceramic Plate Test
This test is conducted with the help of ceramic plate. It is simple test if you are not afraid to scratch your jewellery. Take a ceramic plate, but unglazed; then draw a line with the item.
If you see a gold line, your jewellery is authentic, and if the line is black, your item is fake.
Method 6: Nitric Acid Test
It’s rather dangerous and risky, so you better leave it for professionals.
Nevertheless if you decided to conduct the test at home, you will need the acid. Take stainless steel dish and put the jewellery into it. Drip a nitric acid onto item and wait for any reaction.
The absence of reaction means the gold is real, milk-colored water will become, if your jewellery is silver with plating of gold.
Gold reaction means the item is made from brass with plating of gold, while green color reaction appear when the jewellery is just gold-plated.