"Despite stern warnings, visitors to the Petrified Forest National Park remove several tons of petrified wood from the park each year. Some of them eventually mail this material back to the park, accompanied by ‘conscience letters.’ The content of each letter varies, but writers often include stories of misfortune, attributed directly to their stolen petrified wood."
BAD LUCK, HOT ROCKS:
Conscience Letters and Photographs from the Petrified Forest
Edited by Ryan Thompson & Phil Orr
I’m sorry I picked these rocks up 15 or 20 years ago. I have had bad luck since.