We took an 18kt gold ring to this establishment to sell. Their "expert, who does this for a living" stated that he couldn't do the acid test because he could hardly get the ring to scratch onto the pad. Therefore, the ring was not gold. After we left I found the "18kt" stamp on the inside of the ring. We went back in and showed the stamp to the "expert". Both he and the owner stated that the "18kt" was stamped into the ring some time after it was manufactured. But, the "expert" ran another acid test. This time the ring tested as 14kt gold. We took the ring else where and they ran the acid test in front of us so we could see the results. It tested as 18kt gold.