The 2011 silver eagle anniversary set came with silica packets: Are the packets really necessary to keep with the set if it is kept in a safe deposit box at a bank?
Not the ones it came with, no. Throw them away. Those small packets are soon used up and no good anymore. But, if you wish to greatly lessen the odds of the coins toning, then yes it is necessary to store them in a sealed container with silica gel packs. Hopefully the rechargeable kind. Then you have to check on them once a month or so to see if they need recharging again.
Thanks for your advice GDJMSP. You have helped me out in the past as well and on both counts AGAIN THANKS.