jglunt
Sr. Member
I found this while looking for interesting stones for my tumbler in the Muskegon River here in Michigan. I'm a newbie at this but I'm getting hooked more by the day. The colors in the pics are pretty close and it's the wide non-crystaline layers inside that I find interesting as well as the light, almost white outer color. Any guesses? I tested hardness on the smooth layer and it won't scratch with a knife but does scratch (barely) with quartz. Is it a shale of some kind? Thanks, Jim.