When we buy precious metals, we want to make sure we get the real, authentic metal. We want the real gold. There are many good ways to test for gold.
Caliper Test
Many established branded gold bars or coins has known dimension and tight tolerance levels. For example, a 1 oz Canadian Maple Leaf Gold Coin has a diameter of 30.0mm and a thickness of 2.80mm. A 1 oz Chinese Panda Gold coin has a diameter of 30.05mm and a thickness of 2.70mm. Calipers can reveal any inconsistencies in dimensions, and you should refrain from buying such items.
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Gold Coin CML descriptions[/caption]
Magnet Test
One of the easiest way is to use magnet. Most metals are attracted to magnet, but silver and gold are diamagnetic (metals that are not attracted to magnets) and a magnet will not stick to it. Use a very strong magnet, such as neodymium, to test the gold. If it stick to the magnet, then it is fake gold.
Do note that this is not a 100% foolproof test to determine real gold. Some counterfeit gold are made from metals that are not magnetic in nature.
Density Test
Get an accurate scale and note the weight of your Gold bar.
Get a glass of water, place it on the scale, and set the scale to ZERO.
Tie the gold bar, dip it COMPLETELY into the water, but without touching the base of the glass. The gold bar should be in the middle of the water, note this new weight number on the scale.
Divide the first weight of the bar, by the 2nd weight number (in the water), this number should be 19.30 for an accurate measurement of Gold density. (Pure Gold Density = 19.30 g/cm
3)
Ultrasound Test.
Using special instrument, you can use an ultrasonic device to test for consistency in a bullion bar. Sound waves travel at different speed through different metal. If your gold bar is merely gold plated, the numbers would differ from a pure gold bar of 99.9 purity. The sound velocity for pure gold should be 3200 meters / second (or 0.130 Inch/µSecond)
Porcelain Test
Rub the piece of gold across a piece of unglazed porcelain tile. It should not make a black streak. If it does then it is pyrite. If the streak is golden yellow then it is gold.
Acid Test
Warning: This test is destructive and will spoil a tiny portion of your gold. Please do not use unless absolutely necessary.
Buy a nitric acid test kit. Scratch a surface of the gold piece and add a few drops of the acid on the gold. If it turns green, the item is either brass metal or gold plated. If it turns milky, it is gold plated sterling silver. If there is no reaction, then it is real gold.
Some key pointers before you buy that gold!
- Buy from a reputable merchant. If you buy directly from something like Ebay or Carousell, there are no guarantees that your product is authentic. (www.goldsilvercity.com.sg is backed by a Singapore firm, Newell Builders Pte Ltd, that has been established for more than 30 years. We are here for long term business. Over time, we have many regular gold and silver clients, check the clients' reviews at www.facebook.com/goldsilvercitysg)
- Mints are starting to fight back as well – some newer products have additional security features to prevent counterfeiting.
- Know and understand how the different tests for fake bullion work, and use them to verify that your gold or silver is real.
