The value of gold is based on the karat system, which is a 24-point scale signifying the percentage of gold a piece of metal contains.
So, if gold jewelry is 14K, it is 14 out of 24 parts gold, or 58.33 percent gold
The acid test is the cheapest method used to check gold. Simple acid test kits typically come with a black touchstone and several acid solutions, which are marked for different karats.
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