FLAGSTAFF, Ariz. (AP) - They are called "conscience" rocks and there are piles of them in northern Arizona's Petrified Forest National Park.
Unlike the "pet rock" craze of past years, these rocks aren't keepers.
The Arizona Daily Sun says some of the rocks were mailed back by people citing curses with others seized during inspections.
Some park visitors were caught in the act of stealing. Some of the stone was tossed out of car doors and windows before the visitors who took them reached the inspection station at the entrance of the park.
The National Park Service estimates about a ton of petrified wood a month is stolen from the 220,000-acre park's 600,000 annual visitors.
The rocks once had been wood, part of a large forest that existed 200 million years ago.
Information from: Arizona Daily Sun, http://www.azdailysun.com/
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