The magnet test: if there's iron in it, a magnet will attract it.
The acid test: pure gold does not react with nitric acid.
The density test: pure gold has a density of 19 g/ml which is higher than most metals. 18K gold has a density of 15 to 17 g/ml.
The wear test: if it's just gold plated, the plating may flake off revealing a different color.
Find an area that has been proven to produce gold. Mountainous areas that have strong granite or crystalline deposits are a good start. Areas where geologic upheaval and pressure have occurred is another prime location. Mine the rock from the area. Start with a good amount of rock samples to look for gold ore. Rocks the size of a human hand are best to sample. Look closely for quartz or crystal deposits, since this is where super-heated steam may have driven gold into "veins" of gold ore. Test the waters of any nearby streams or rivers. Gold ore can be washed many miles from its source and lodge under river rocks and obstructions. Take a sluice pan and sample the sand and silt from the riverbed near boulders and river bends Search through the discarded heaps of waste materials from old gold ore mines. Many old abandoned gold mines that flourished during the "gold rush" era have waste deposits that may contain viable amounts of overlooked gold ore hopes this helps
There are a few tests you can try using to test the purity of a gold piece:
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