Bringing rockhound site guides into the 21st century, Roadside Rockhound features up close site info, including lodging and map links.
If you're looking for information on your local Gem & Mineral Society, you'll find it here.
If you're in California, and looking for information on your local Rock, Gem & Mineral Club, here's the place to find it, and lots more info!
You'll find useful map services of all sorts at these sites.
Here's the go-to source for all types of geologic maps, with a fully interactive database.
Most U.S. States are represented, and many States have contributed the maps from their State Geological Survey units to the database.
TopoQuest is my favorite online topographical map service. It features an excellent user interface, with intuitive controls and a good search feature.
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