At my workplace we receive lots of rolled coin from the bank each week (at least $1000 in quarters, nickel and dime bank boxes on a regular basis). Given that I can't open all these rolls myself, are there any devices or methods to detect silver coins in a sealed paper coin roll?
Well, the only thing you could really do that I am aware of is by weighing the rolls with a small scale that can measure up to hundredths of a gram. Calculate how much a full roll of solid clad dimes and quarters weigh and then look for rolls that weigh a little more than usual. You might feel it is too tedious to check rolls without opening them considering that 1 silver dime is found per box on average and that silver quarters tend to turn up even less frequently but it might be something to consider trying.
I don't think it would work too well. The difference in weight between silver and clad dimes is about 0.23 grams. The variation in weight of a roll of 50 clad dimes would more than cover that.
What about conductivity? You could insert the probe of a multimeter into each end of a roll to measure Ohms. I don't know what the difference in conductivity between silver and nickel is, but I suspect silver is higher (which is bad for this scenario). Factor in the varying amounts of grime found on the surfaces of nickels, and I've probably already debunked this as a possibility. I just thought I'd throw it out there in case someone knows better than me that it is possible...
I thought about this, but as I'm working in an office situation, any device needs to be very small. Is there a such thing as a pen-sized or handheld metal detector?