A quick list of references or websites we enjoy and have found useful. Also,d on't forget that our blog has a lot of quick tips & tricks for you as well.
The Moh's Hardness Scale - Excellent resource for sorting stones and figuring out exactly what you can mix together in your tumbler.
GeologyPage.com -- Another great resource for learning about the Moh's scale.
Geology.com - TONS of fantastic information here!
Bedrock Supply - A great source for beads, wire and jewelry supplies.
Rock Tumbling Hobby Forums - An EXCELLENT resource for anything lapidary and full of amazing people.