I went to an estate auction and picked up a whole 55 gallon drum of tumbling rough. Pieces anywhere from fist sized to very small chips. Some of the larger pieces could still be cut up if you like, or broken down farther if they are too big for your tumbler.
The material is mostly jasper and agate with lots of different materials in there. In sorting through the material I have seen Bruneau, Stone Canyon, Texas Springs limb casts, Ochocho Moss agate, Carey moss agate, Amythest Sage, waterline agate, petrified wood, Tigereye, Mookite, Spiderweb jasper, Rocky Butte, Wild Horse, Original Owyhee, Snake River Agate, Owyhee blue opal and lots more stuff that I am not sure where it came from.
I will fill a regular sized flat rate box just as full as I can get it, should be somewhere between 25 and 32 lbs, depending on the material that gets put in and how well it all fits together.
First 2 pics are dry, rest are a 5 gallon bucket sampling taken wet on the tailgate.