Whatever it is, I like it. I'm wondering if could be slag glass from an old iron furnace? I found what I first thought was blue obsidian locally only to find out that it was slag. You might want to move this to the "Rocks and Gems" forum.
I have seen a lot of Trinitite that looks just like that, but if it didn't come from somewhere near an Atomic Test Site (READ: New Mexico), its not likely to be Trinitite. Most likely glass slag or an old melted coke bottle. It has the exact same coloration as an old coke bottle.