I recently purchased some tubes of 1 oz. silver rounds from a local dealer. I have checked each round as best I know how: weight - varies from 31.10 g to 31.58 g (the heavier ones seemed to be in the same tube); dimensions - don't exactly match what the mint publishes (published diameter 39.3 and thickness 3.2, actual diameter 39.2 and thickness 2.9 to 3.0); magnetic slide - all pass; ping test - used Android Bullion Test app and all except two checked out; specific gravity - random sampling checked out at 10.48 to 10.5 (even with the two that didn't pass ping test). So I have some questions that I hope someone more experienced than I am can help me understand: 1. Is it normal for mints to produce bullion rounds that vary so much in weight and differ from published dimensions? 2. Is it possible to make a fake silver round that passes the magnetic slide and specific gravity but still fails the ping test (perhaps using an antifriction metal which has specific gravity of 9.3 to 10.6 and either tin or lead based would have diamagnetic properties)? 3. Are there any other tests I can do? Thanks for any help you can offer.
The weight variance is not anything to worry about, the size isn't that big of a deal either! Most likely they're legitimate generic silver rounds. Golden State Mint is a reputable minting company last I heard! If you still have doubts, take it to a coin shop or jeweler who has an XRF scanner and have them scan a couple!
Due to it being bullion and not a coin, you could do the acid test. Using the edge of a rim, simply rub it on the stone and apply the acid to see if it is real silver. There are other ways and here is some. https://treasurepursuits.com/how-to-test-silver/ https://www.silverrecyclers.com/blog/how-to-test-silver.aspx
Golden State is a reputable company. Nothing you mentioned, the size and weight, alarms me. Do ask yourself, is the dealer so bought these from a dealer that can be trusted? Are they a reputable dealer?
