If this STORY is true, the grandson is pond scum for selling the silver certificate! Maybe he should go to his Grandfather's grave site and dig the old fella up, section him up and sell the bones, mounted in gel membrane boxes, along with 1mm x 1mm pieces (Bessy Specks) of the silver certificate. The seller could include post cards of a meteor shower from the era and double his money. We can only hope that Grandma remains in the quiet safety of her grave.
High Regards, Fred Hall
