Archimedes is a scientist famous for discovering that when you immerse a body in a liquid like water it loses the same amount of weight as that of the fluid it displaces. We now refer to this phenomenon as the Archimedes principle. His might be a name more familiar with people who study physics, most people aren’t familiar with his name or his principle but they are familiar with the term Eureka! What most people don’t know is that Archimedes wasn’t just sitting in a bathtub when he was struck by this sudden realisation. Archimedes was pondering a way to determine if a certain golden crown was indeed made of pure gold and not some amalgam of gold and silver. Archimedes succeeded in figuring that indeed this golden crown wasn’t made of pure gold as everyone first thought. Thanks to scientists like Archimedes, we are able to tell whether we have real pure gold or not. There are a lot of cheap imitations of the yellow metal on the market, it can be hard for the ordinary people to tell what’s real and what’s fake. If you are looking to sell gold there are a few things you can do to test its purity and avoid being turned away for selling fake stuff.

1. Do a density test

Archimedes’ scientific endeavours proved one way of testing gold. Thanks to him we know that gold is denser than most metals. Gold will not float in water but nor will a number of metals. When testing density, you aren’t trying to find out if something will float or not, but how much water it is able to displace. If you put a piece of gold in a glass of water the water level will rise. Note the level before the gold is put in the glass of water and the level the water rises to after the inclusion of gold. To work out the density take the weight of your gold item and divide that by the difference in the water level. If you come up with a value that is close to 19.3 g/cm3 (which happens to be the density of gold) then Eureka you have a genuine gold item in hand.

2. Take a bite

Have you ever wondered why Olympians gold medal winners always take a bite of the metal? To test if the metal really is gold. However, gold is quite soft, especially the high karat gold. Your teeth are likely to leave marks when you bite into real gold. Just don’t bite too hard, gold is still relatively hard and it might chip your teeth if you bite hard on it. When sell gold you should check how authentic it is. Athletes aren’t be only once who have a habit of biting their medals, the practice of biting into gold goes back to the olden days when miners would bite at the mineral to test if it was the real deal or just a hunk of pyrite (fools gold).

3. Look carefully

Take a good look at your gold, often there will be an inscription or stamp indicating the karat of your gold. Look at the colour as well. Fake gold tends to develop a sickly green colour. Gold plating also wears off with constant friction.