To the best of my knowledge, gold is still tested with a touchstone & nitric acid in higher & lower concentrations is used, for very high content gold aqua regia is used.
However, for silver we use a test fluid that is applied directly to the metal, just one drop, & the metal turns red if it contains silver.
This is not a precise test like the gold, so we do not know the silver content, to ascertain accurate silver, content other methods, including laboratory analysis are required. Silver is nowhere near as valuable as gold, & for the small items of silver that we normally need to test, the cost getting precise silver content would outweigh the value of the silver.
A little bottle of silver test fluid costs only a few dollars will last for a very long time.
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