Knowing if a coin is fake or not can be determined with a few easy tests
When you have gold or silver coin or bar and you want to know if it’s fake, here are few quick accurate tests you can do at home.
Here is what is required to do all tests
- A quality scale to verify the weight that will go to .01 of a gram or troy ounce. Also .1 of a gram is also okay
- Vernier calipers or accurate measuring device. Strongly recommend digital vernier calipers that go to .1mm accuracy.
- A small rare earth magnet 5-8 mm diameter x 4-6 mm high for the “Slide Test”
- A medium rare earth magnet 10mm wide x 6-8mm high x 40-50mm long for the “Wave Test”
Measurement Test – Weigh the item and ensure it matches the exact weight the coin is stamped with e.g. 1 oz, 1/10 oz, 10 oz. The weight should not be less, and not grossly over. Check the physical measurements are exact to what the manufacturer or mint publishes.
Weight test – I have seen too often a copper clad bar with silver weight the right weight, however the size is bigger than it should be. That is because the specific gravity of the filling metal cannot match that of gold and silver.
Their are two simple tests you can do with a strong rare earth magnet to confirm that your coin or bar is not fake gold or silver.
Magnet Wave Test – First get yourself a strong medium sized rare earth magnet, you can buy or use from any electronic device like hard drive. It will be like 10 times stronger than a normal magnet attraction. With out touching the magnet onto the coin or bar, keep a gap of 2-3k and wave the magnet across what you are testing. If the coin or bar is solid precious metal, you will feel a good repel, note it’s a repel and not an attraction. The repel is usually strong enough to move a 1 oz coin or bar around a bench or desk top. If you wave the magnet over your item and you have no repel feeling, it’s a good chance the item is not high purity and could be plated.
Magnet Slide Test – This test is one of my favorite’s for silver testing bars that are 10oz or larger, however can be use with effect on smaller gold and silver coins. You get a rare earth magnet that is small is size e.g. 5-8 mm diameter x 4-6 mm high, not these have a strong magnetism like the magnet mentioned above. To test the metal piece, first if you don’t want to scratch your piece, then consider to cover your item with something very thin. You hold the coin or bar on a 45 degree angle, and place the small magnet at the top and allow it to slide down. The magnet should move at a much slower pace than gravity. Eg if you I the same with a book, the magnet races away. If your item is high purity gold or silver, it will have a repel effect which will cause the magnet to travel down the item much slower.
Getting the desired results from these simple tests is a very easy way to check if your item is indeed containing high purity gold or silver (eg 999, 9999, 99.9%, 99.99%
If you are still not sure, then its recommend to take it to one of your closest coins shops or gold dealers to have them verify with a XRF analyzer that accurately test the precious metals content.
Here are AuNaG we use all the methods above to test precious metals, and we are always validating our inventory with or XRF Precious Metals Analyzer.
Some important considerations to remember each time you test for fake coins and bars:
- Mints don’t put less than the indicated weight into their products, you will very very rarely see an item marked 1 troy ounce and the weight be under that.
- If the silver is tarnished or milk spotted, this typically indicates silver is present, and may strengthen your analysis if the item is what you are testing for.
- If you observe the color of an orange tinge showing through the silver, this could be a good indicator the bar is copper filled.
- If you overserve the color of green tinge in the gold coin or bar, this could be a indication the gold is alloyed with copper or could be copper filled.
- An obvious and important point is to get your precious metals from a reputable supplier. Don’t be a statistic that gets scammed.
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