Welcome!
Some pictures would help, but you need a little more interaction on the site before you're allowed to do that - description next. Meanwhile, some idea of location (ie which continent) would give some context.
They sound like ingots; probably minted (if they are cast they will show swirls). Ingots or bars normally attract a modest premium over spot (say 5%) - so multiply the 1 Oz price from the charts by 10.5 and you are good to go. Having said that, 10 Oz (note that these are Troy Oz) are a popular size, and some older bars have additional value. (sorry - I was working from an old window, so missed the preceding information. I'm guessing you are in the US)
You could sell them for a family dinner, tuck them away in case the Silver price keeps rising (most of us hope so) or start looking at other stacking options including more bars so they don't feel lonely. I suggest the latter, in which case introduce yourself at Welcome New Members and see how the mood takes you. By the way; until you have a little more knowledge, it is a good idea to keep your specific location and stack size obscure - no point in giving thieves a treasure map. See also 'Bizarre Boating Accident'.