I dont know much about geology/rocks/gems. I found this rock in a river. Its about the size of a quarter black and rough with little holes that are shiny black like obsidian. Can someone tell me what it is. I will post a picture as soon as I can
The streak will be the color of the stone however what you'll be looking for is going to be a grainy line that looks like little bits of fractured glass. It may or may not streak on porcelain but because it does fracture easily you should see what I'm talking about.
Obsidians can be found in that part of the country. But as pointed out by BB it could be slag glass as well. Lots of bubbles in it where as most obsidians are fairly solid.