The other day my friend was in a big dilemma. The jewelry she wore, which she knew was made of gold, was challenged by someone – that it was not right, it was false. How do you find it? Here are the roads:
On the back of your wrist dab a small liquid foundation. Brush a few kinds of powder. Rub the affected metal onto it. We were told that real gold will show black marks. But since much rubbing is involved, the skin gets irritated in some way, so even though this is a simple test, we couldn't really trust one hundred percent on this one.
Zinc and flow test:
The gold is heavy, so if the metal in question is liquid it is definitely false. But then depends on the shape of the jewelry, even brass or other metal can sink. Therefore, it is not a silly proof either.
Take a magnet near gold jewelry in question. Gold will not be attracted by magnet but its alloys can. Again, since gold jewelry has a little alloy, we cannot be completely safe.
Gold is softer and more malleable than anything else. While other fake metals may break, gold will not. So touching or dots with a pin can give some clues.
If the metal in question is affected by a drop of nitric acid, the following results may give us a clue.
If it is pure gold, there will be no change. The gold passes the oxygen test. If it gets green it is definitely false. If it gets a little green it means that there is some alloy that is natural. If there is milk foam, it is mixed with silver, or the metal may be superior.
Pure gold is 24 carat gold and to make gold jewelry it needs to be mixed with any alloy or impurity. Now each carat is about 4,167 kg of gold. Thus, a 22k bit 91% gold, 14K bit is 58% gold. Everything over 10k is considered gold in the United States. Different countries have different acceptance rules for gold. In the United States, you can't sell anything less than 10k if you want to call it gold.
Although test kits are available in many jewelry stores, (they are around $ 20- $ 30 in price range) this nitric acid is quite dangerous and I'd rather have a professional person or jewelry store do it. When higher carat gold is used, Aqua Regia is usually used instead of nitric acid.
Jewelry stores can probably also help you find out if there is a 22 carat gold part, 18 carat or less carat ones because they have gold pieces with known carats. A sample made with a touchstone (a special type of stone) and acid solution may find out the result.
I have written more about this type of test on my website along with information on gold or gold-filled and gold-plated metals.
Hope this gives you a clue how to find real gold from fake. Again, the best thing when you are in doubt, take it to a good, trust a worthy professional jeweler. Usually they are helpful and can show you the result.