The weight of Gold is brought about by its high density. Each atom of gold is very heavy on its own, making the element heavy too. Unlike other elements that are as heavy as tungsten, gold's atoms are not so bonded to each other making it less brittle and easily shifted and shaped when working on it.
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.
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. Its density is lower: 14K – 12.9 to 14.6 g/ml, 18K – 15.2 to 15.9 g/ml, and 22K – 17.7 to 17.8 g/ml.
A cubic foot of iron is 491 lb. A cubic foot of copper is 559 lb. Silver is even heavier than copper, at 655 lb for a cubic foot. Gold is really heavy at 1206 lb for a cubic foot.
Osmium is the most dense metal! Many people are familiar with lead (11.3 kg/L), but osmium is twice as dense (22.6 kg/L)! Each liter (about 1/4 gallon) of osmium weighs 22.6 kg (50 lbs).
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. If that necklace leaps to the magnet, your significant other has some explaining to do.
Gold is called a heavy metal because of its high density, which comes from the fact that each of its atoms is individually very heavy. The density of tungsten is almost identical, but tungsten is hard and brittle because its atoms are tightly linked and it is difficult to force them past each other.
To find the density of your gold item, divide its volume by its weight. For example, if your item weighs 40 grams and has a volume of 2.2 milliliters, its density will be 40 / 2.2, which is 18.18 g/mL. Since the density of gold is 19.3 g/mL, the chances are your item is mostly real gold.
Look for Stamps or Hallmarks in Your Gold Jewelry
Most real gold is stamped with a hallmark that indicates its purity, aka its karat. The karat is the unit used to measure the purity of gold. The higher the karat, the purer the gold. The most common karats you'll see are 10k, 14k, 18k, 22K, and 24k.
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.
Although it is very strong, gold is the most malleable of all metals. Pure gold is too soft to withstand the stresses of everyday wear, so it is combined with different alloys to give it strength and durability. These alloys include metals like silver, copper, nickel, and zinc.
Note: * Caesium is the softest metal with the Mohs hardness of 0.2. * Always remember, the hardness of gold, silver, aluminium, zinc, lanthanum, cerium, jet is in between 2.5-3 and that of platinum is 3.5 (according to Mohs hardness).
The Nitric Acid Test
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.
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.
Hold your metal object firmly in your hand or set it on a table. Place a few drops of vinegar onto the object. If the drops change the color of the metal, then it is not pure gold. If the color stays the same, then it is pure gold.
Weight. A good way to tell if 18k gold is real is by its weight. Gold is a heavy metal, so heavy that it will sink in water. If you drop your jewelry in a glass of water, real gold will drop straight down.
Fake gold pieces may have a heavier weight but also be too large for the weight to match the weight of real gold. Check the diameter and thickness of any gold coins you're considering buying.
An acid test can reveal the karat of solid gold jewelry, but it can also show whether jewelry is solid gold or gold-plated. With an acid test, a small sample of the jewelry is removed and exposed to acid to induce a color change. The resulting colors indicate which type of metal the jewelry is made of.
Gold is a particularly non-reactive element and is not absorbed during the digestion process, so it is safe to eat. However, there are no nutritional or health benefits associated with its consumption.
The most common mineral mistaken for gold is pyrite. Chalcopyrite may also appear gold-like, and weathered mica can mimic gold as well. Compared to actual gold, these minerals will flake, powder, or crumble when poked with a metal point, whereas gold will gouge or indent like soft lead.
One way of telling if your jewelry is actually gold is by using a magnet. If your gold is magnetic, then there is iron or nickel inside of it. Pure gold is not attracted to magnetic fields, but if an enormous magnetic field is applied to gold, the gold will slightly move and then slightly repel it.
Aim to get 90 to 95% of the spot price when selling gold bars or coins, and 70 to 80% of melt value for jewelry and other items. A karat is a unit of measure for the fineness of gold. For example, your 12-karat gold band is 50% gold. An 18-karat gold band would be 75% gold.
Pure gold on its own cannot stick to a magnet. However, if you have an alloy of gold, then it could stick to a magnet. An example of a gold alloy that may stick to a magnet is gold with over 20% of its atoms replaced by iron. In very cold temperatures this alloy of gold may magnetize all on its own.
You can also fill a cup or glass with white vinegar, and drop your gold in it, let it soak for 5-8 minutes, take it out and rinse with water. If the metal has changed its color even slightly, then the gold is not pure but if it keeps shining, then the gold is pure.
Be sure to use plain white toothpaste; avoid any with colored stripes or other added ingredients. Rub the toothpaste onto the gold for about 30 seconds. You should see a black streak begin to form.