How to identify the Purity of Gold?

Not many of us might know that what we might perceive as pure gold in the form of coins, jewelry, or showpieces could, in fact, have other impurities as well, and no, we are not talking about the necessary impurities that are added to make the article stronger (the reason why jewelry is available in 22 karat and not 24 karat), but excessive forms of impurities to increase the seller's margin and to increase the weight of the gold item being sold as well. Following are some tests to help you check the purity of the gold item you are about to purchase, or have purchased.


The Sink and Float Test:

Gold is a heavy metal, and it is quite obvious that when placed in a tub or bucket of water, the article in question should sink to the bottom. However, there are lighter alloys as well that are added, so it basically depends on the size of the item. If it is a gold earring or coin, this test might not prove to be the most fool-proof one, but in case of heavier items like necklaces and showpieces, this test is a preliminary necessity.


The Magnet Test:

Gold is not attracted to magnets, but some of its alloys are. Hence, if you bring a magnet close to the item and it instantly grabs hold of the article, it means that the percentage of alloy in the item has a tendency of being more than required. But again, this is also totally depending on the size of the article, and its stated purity (An 18 karat item would definitely have a higher amount of alloys as compared to a 22 karat item).


The Rub Test:

A rather unusual test, it requires you to rub a little foundation on the back of your wrist, followed by a few brush strokes of powder, and rub the gold item on it. Real gold tends to show black marks, whereas a fake artifact would not.


The Acid Test:

If the item comes in contact with nitric acid and does not show any change, then it is definitely pure gold (24 karats). If it turns green, then it is a fake for sure. If it turns slightly green, then there is a certain percentage of alloys, which may be acceptable depending on the item. And if the nitric acid turns into milky froth, then either it is mixed with silver or vermeil.