Here is a
great video how to spot fake silver bullion...
https://www.youtube.com/watch?v=_rjJmGGkNPU
These aren't baseball cards that can be altered in many different ways - trimmed, re-colored, rebuilt corners, soaked in chemicals, etc.
We're taking silver bullion and coins. They're either silver or they're not.
If you're interested in an acid test kit, here's a good one for starters.
https://www.ebay.com/itm/Silver-Test...72.m2749.l2649