These dry wipes work, but they are teeny tiny and unnecessary for the most part since you can make a silver cleaning bath yourself. Here is how to do it: Put aluminum foil in a bowl or glass. Pour baking soda and kitchen salt (ration is irrelevant). Pour very hot (but not boiling) water in the glass. you will witness a fun chemical reaction. Now you have a silver cleaning bath. Place your jewelry in it. I have a silver ring with a fake diamond and it cleaned it in no time. The fake stone is fine. I also cleaned a charm with mother of pearl in it and it looks great. So although I like these wipes I see no reason to purchase them when I can do it for free.
If you are interested in chemistry, here is what is going on when your silver jewelry is taking this little "bath":
Silver sulfide is the stuff that makes your silver look grayish over time. This process is called oxidation. When immersed in the baking soda/salt solution, the aluminum reacts with the silver sulfide, pulling the sulphur atoms out and "plating" them onto the aluminum as aluminum sulfide. The silver that remains from the reaction is redeposited onto the silver.