I have alot of black stone along with a ton of old artifacts from 1890-1930 under a crawl space of an old building. With this is alot of what looks like shiny black rock. It's very brittle and as it breaks it feels and looks like glass. Any idea?
This appears to be coal, which is commonly found around, and under, buildings from the 1800s and early 1900s. My farm is littered with it and it is especially common around the foundation of our 100+ year old farmhouse. It does often have a glassy texture and can be quite brittle. Be sure to keep an eye out for bottles in that crawl space! Those are my favorite treasures to find.