I recently stopped at a used book store and purchased a 1958 Hardback edition of the Carroll Fenton- "The Fossil Book", which is a great book if you have not seen it before. Inside the book I found the attached 4 1/2 " by 7 " card, warning about "Rock Pox"; which I think all of us suffer from. The store that the card came from (Mid-America Rock Shop- Chicago) is also a fossil, and I would guess that it has not been around since the 70's. Enjoy.