Gold is one of the most valuable of all metals. Not only is it a sign of money, but also stability. If you are planning to invest in gold or you enjoy buying gold jewelery, it is important to know how pure what you are buying is. The easiest thing to do is to take the gold to a jeweler, but there are some tricks that will give you a fair idea of the purity of the gold you are buying.

Mohs Scale Test

The Mohs scale was devised by Friedrich Mohs nearly 200 hundred years ago. It is a relative scale that tells you the hardness of various metals and minerals. Gold has a hardness of about 2.5 to 3 on this scale, while glass has a hardness of 5.5. Therefore, to ascertain whether the metal in your hand is pure gold, try scratching glass with it. If it manages to scratch glass, you can be quite sure that the metal is not pure gold. There's some amount of impurity mixed in it.

Checking the Density of Gold

Checking the density of gold is one of the more accurate ways of finding out whether the gold is pure or not. In order to accomplish this on your own, you will need a graduated cylinder and a scale. To begin, first determine the mass of the gold in grams by weighing it. Next, fill some water in the graduated cylinder. There is no fixed amount of water that needs to be filled; however, make sure that you don't fill it to the brim. Note the amount of the water in milliliters. Next, drop the gold in the water and note the new level of water. Note the difference between the earlier reading and the current one. For example, if the water was at an original level of 10 mL, and after dropping the gold in the water it came up to 12 mL, the difference between the two readings is 2 mL. This figure is known as the volume of displaced water. To make the calculations, you need the two figures: the mass of gold and the volume of displaced water. Use the formula Density = mass of gold/volume of displaced liquid. If the answer works out to about 19 grams/mL, the gold is, in all possibility, real.

Some Easier Tips

Apart from these tips that require scientific expertise, there are a few others that can be employed to check whether your gold is real. One of them is holding the gold near a magnet. If it gets attracted by the magnet, it is not pure gold, and there are traces of other metals mixed in it. Another method you can employ is to rub the gold across a piece of unglazed ceramic material. If you notice a black streak, it is fool's gold. And if you notice a golden streak, it is indeed, pure gold. Finally, you can even test it with hydrochloric acid. Just drop a tiny amount of it onto the gold. If it shows signs of dissolving, you will know that it's not pure gold.

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Gold Purity

How to Tell If You are Buying Real Gold Jewelry