SILVER Gold testing acid 2 bottles. Is your Silver real or fake? What is the Silver content of your jewellery?
Each 20ml bottle (40ml total) comes sealed and contains enough acid for hundreds of tests.
You will receive 2 SILVER bottles and a rectangle lydian testing touchstone 7cm (h) x 4cm (w) x 1cm (d). 
The bottles are designed to easily dispense one drop at a time.
Instructions (see 3rd image in the listing).
The colour reaction of the solution with the metal scratch will be as follows:
(take into consideration that the background of the testing stone is black).
Fine silver .999 = bright red.
Sterling silver .925 = dark red.
80% silver purity .800 = brown.
50% silver purity .500 = green.