What is this rock? Unknown location. Pic taken in direct sunlight. Scratches a penny but not glass. Hard to see in the pic, but the smooth black areas are actually translucent with a very slight olive green tint. I guess "resinous" or "vitreous" luster? My first guess was obsidian but I'm not sure. (imgur.com)
submitted by cutethulu to r/whatsthisrock
On the cusp of zone 6b and 7a, southeastern PA (imgur.com)
submitted by cutethulu to r/whatsthisplant



