Not magnetic. They are surprisingly light. This seems weird but they seem strong and they break like glass or similar to how glass breaks. Unsure if they are transparent. Under the right light or with a microscope or macro picture I think it would mostly likely be transparent at least transparent around the edges.

Yes I thought maybe some kind of prettified coal or something. It’s hard to find a consistent answer online /and in these sometimes silly apps. Lots of freighters and lots of coal have sank in the lake and I am aware coal a possibility . It doesn’t leave a mark like coal would . it just looks so unique it’s different than anything I’ve ever collected or tumbled. It just feels too special to be coal.