How do jewelers measure gold content in jewelery?
There are electric meters that measure gold purity. They are not perfectly accurate, and some effort must be taken for gold plated items. They are very fast. If your coin is of a commonly recognized type, they may accept the labeled purity. If it looks homemade, they will be rightfully suspicious. I don’t know if jewelers use the density test, but it takes no highly specialized equipment. I don’t like the scratch test myself, but some jewelers may use it. None of these methods take more than a minute or two. If they have to melt it down, which is very unlikely, that would take time.
