about the black slab---Produced in 2012 to commemorate the 25th anniversary of the original Gen 1 black holder. These black insert holders were available alongside the standard white insert holders on certain denominations of
US coins. I thought they should be recognized along with the standard white holders, so I am calling this black insert holder Gen 14.1. I've left out black holders of later generations as they were used almost exclusively for bullion...Rarity~Occasional