Okay, I'm back. Despite some serious airline hiccups we eventually made it to the Yellowstone river. Thanks again to all who helped with the suggestions (particularly Montana John) on where to go. Some areas we found a fair amount, other area we found next to nothing. The worst places of course were where it was easy to access and had been picked over.
Petrified wood (black and gray) is super easy to find. We stopped picking that up pretty quickly. I found some of what I think was also petrified wood with some yellows and reds in it, even one that I’m pretty sure was fossilized coral. Not sure how that will polish up. Total we brought home was about 70 lbs. That was 2 people looking for about 1 ½ days. Probably 2/3rd of that was Montana agate, and probably 1/3 of the Montana agate was nice material. We picked up a fair bit of Montana agate that seemed to just be clear. I've heard tell about the "iris" Montana agate. Do you just get lucky on this with the clear pieces, or is there a method of determining if a piece will show the iris effect, and any tips on how to cut it to display that effect?
I’ll post some photos below. I particularly like the one that looks (to me anyhow) like a bear. I’ll probably cut that one and polish it for a mantle type piece (started on it last night).
After the collecting we went to Crystal Park for a day. Fun digging and beautiful, but we did not find any large crystals. Afterwards we went backcountry camping/hiking in Glacier National Park. A lot of work carrying all your gear up/down the mountains. Saw lots of goats, and even one grizzly bear.