Alison Jean Cole is a lapidary in Portland who cuts stone for a living, guides rockhounding trips, and puts out a zine called Thunderegg about where the hobby is headed. Most rock guides hand you a list of famous sites by state, which is how those sites get picked clean. She does the opposite. This one teaches you to read a geologic map, figure out what the ground under you is made of, and go find your own spot, so it works anywhere in the U.S. or Canada. She’s straight about the ethics too — what you can legally take off public land, what to leave, and how not to wreck a place for whoever shows up next. There’s a good section on figuring out what you actually like instead of grabbing everything shiny. Fifty-eight color photos, 208 pages, and it’s a how-to-think book more than a where-to-go book.