Boy, rocks will fool you. I've slabbed some really nasty looking rocks and had them be gorgeous inside, and just this week slabbed a big rock I thought was going to be great but it's not what I thought it was.
The Tampa Bay Mineral & Science Club has this rock pile. People toss stuff out there and others of us dig through it.
Two Saturdays ago I was digging in it and came up with about a 15-pound black rock. One of the instructors said he thought it might be black jade, so I carried it and several smaller rocks home and slabbed them to see what was inside.
I could just barely vise the big black rock, and it took me three days to break it down completely into slabs. The more I cut, the more I felt that it's not jade but flint. And when I took some of the slabs in to the club last night, the instructor looked at it and agreed with me.
So now that begs the question, how will it polish? It's a deep enough black that it still might make some nice cabs. But goodness, I have a lot of it!
Then there was this other rock. Heavy for its size but not heavy enough for hematite. Yet the rust lines in it indicate that it probably contains some hematite.
This one generated some head scratching. Finally Greg and Charlie, after studying the slabs and conferring over them, came up with the idea that it's probably a meteorite that someone tossed into the pile without knowing what it is.
They want me to polish a piece of it so they can put a drop of nitric acid on it and see what happens. I don't know the "whys" yet, but I'm going to try to get one small surface polished tonight and then see what happens. This could be cool.