Yes, I called the company that makes them. I just had a normal question. The receptionist gave my call to the owner/inventor. We talked a while and said he had a "secret" he does not advertise because every machine is slightly different on silver (but exact on gold) Here is what he explained. Take several items that I know is silver and test them. Record the digital readout numbers. Pick the high and low numbers, that will be your silver range. So on my machine 230 is iffy and 250 on up to 310 is silver.
I really can't say on the internet. But it was fruitful. What isn't in my safe deposit box at the bank got melted and paid for a lot of my daughters last years at college.
yes, it slides into the black tube that touches the jewelry. it is a bout $15.00 ea on ebay. it will do a few hundred tests. I squeeze out about half a drop for each test. the instructions reccommends a full drop. this is how I do it.
