You've decided to select a rock to turn into jewelry. Simple, right? Not so fast! After decades of rock collecting, I know that it can be difficult to pick the right stone. Or to pick only...

You spot a stone. It's beautiful! Then you wonder: is it is okay to collect it? The answer is that it depends. There are places in the U.S. where it's totally okay—and even encouraged!—to collect rocks, as well as places where you should never...