Place your jewelry on a table or hold it in your hand, pour some white vinegar on the metal directly (a dropper can also be used) if the metal of the jewelry changes its color, it is not pure gold and if it keeps shining then you have real gold in your hand.
You need to weigh the gold and then measure its volume by immersing it in a container filled with water. The density of the gold can be calculated by dividing the weight by the volume. The purity of the gold can be determined by comparing its density with the density of pure gold.
How to Do the Float Test to Check If Gold is Real. Fill a cup or bowl with water and carefully drop your gold piece into it. If the gold is real, it will sink to the bottom of the cup. If it's fake, it will float to the top or hover in the middle of the cup.
Gold is a noble metal which means its resistant to corrosion, oxidation and acid. To perform this test, rub your gold on a black stone to leave a visible mark. Then apply nitric acid to the mark. The acid will dissolve any base metals that aren't real gold.
What to do: Hold the magnet up to the gold. If it's real gold it will not stick to the magnet. (Fun fact: Real gold is not magnetic.) Fake gold, on the other hand, will stick to the magnet.
Fool's Gold can be one of three minerals. The most common mineral mistaken for gold is pyrite. Chalcopyrite may also appear gold-like, and weathered mica can mimic gold as well.
Test Gold Using the Float Test
Take a cup or glass, fill it up with water, now bring the gold that you want to test. Drop it into this filled glass. If the gold floats, it is surely not real but if the gold sinks to the end of the glass then it is pure gold. The real gold will sink due to being a heavy metal.
Heat your gold jewelry with the lighter.
Apply the flame to the jewelry for about a minute or 60 seconds. Watch it closely for any changes in color. Fake gold will get darker, while pure gold will do the opposite: it will get brighter the hotter it gets.
If your gold piece turns black or green when the vinegar is on it, or if it starts to smoke or fizzle at all when the vinegar touches it, it is most likely not real gold. If your gold piece does not change colors and does not fizzle or react to the vinegar in any way, it is probably real.
Step 1: Bite Down On It
If it's real gold, your teeth will form small dents in the metal. Fake gold won't dent at all on a bite test! Now, before you chip a tooth, remember that gold is a soft metal so there's no need to bite down very hard.
To test a rock for gold, first perform nondestructive visual inspections and tests for weight and magnetism. You can also use destructive methods such as testing hardness, streak, ductility, or pulverizing and panning the powder. You will need a scale, glass, unglazed ceramic, and a powerful magnet.
Although most gold bars are made of high purity, usually bearing 99.9 per cent fineness, raw gold isn't as pure. Since it comes straight from the earth, it is alloyed with different metals that are usually refined to produce pure gold.
Drop a small amount of liquid nitric acid on that scratch and wait for a chemical reaction. Fake gold will immediately turn green where the acid is. Gold-over-sterling silver will become milky in appearance.
Gold is classified as a heavy metal despite its softness and malleability because each of its atoms is heavy on its own. It is a dense material.
The Float Test
Place your gold piece into the water. If it's genuine gold, then it will immediately sink to the bottom of the cup. Pure gold is heavy due to its high density – 19.32 g/ ml. If your gold item floats or hovers above the cup's bottom – it's fake or plated gold.
Raw gold appears brassy yellow and bright. If you think it is gold, place your hand between it and the sun to create shade over the gold. If it still appears bright in the pan, chances are that it is real gold. Fool's gold does not appear as bright when shaded.
The color of pure Gold is bright golden yellow, but the greater the silver content, the whiter its color is. Much of the gold mined is actually from gold ore rather then actual Gold specimens. The ore is often brown, iron-stained rock or massive white Quartz, and usually contains only minute traces of gold.
Real gold, on the other hand, gives off it's beautiful, soft shine whether or not it's exposed to light.