Hello,
I'm considering purchasing some unopened Mazon creek nodules to open for fun, since I'm unable to hunt fossils myself. I'm inexperienced with the material so I wanted to ask if there is a rule of thumb for judging if a nodule is going to be good or potentially contain some rare stuff?
Here is an example batch I'm considering. The nodules range from 4-8 inches. My gut tells me the very long thin ones are most likely the common plants like Pecopteris, and that I should try to get more of the round/oval ones?