when I first found the banded stuff, I thought on the same lines as you, but than a friend said they are stromatolites. but I can't explain to myself the "swirl", the bands display at the 1st pic.
pic 3 though is petrified wood, and I think the quality and colour of it, makes you think otherwise. the specimen is harder than glass, and would be ideal for flint napping. I am wood worker by trade, and I can clearly, make out year rings at the ends, but it sure doesn't look like most other petrified wood, I have seen. it for example doesn't display a single conchoidal fracture...
cheers for your input!
I will upload more finds from this spot in given time.