Location: Found on the side of a road near fields/farms in South Wales, UK.
Physical Properties:
- Hardness: I tried scratching it with a steel knife using a lot of pressure, but it left no marks.
- Transparency: The main body is opaque, but the very thin edges show a slight brownish transparency when held up to a light.
- Texture: It has a very glassy feel in sections but is "rocky" in others.
- Notable Features: The most interesting part is the layering. On close inspection, the layers appear to be made of lines of tiny "dots" or small crystals.
I'm curious if this is a natural volcanic glass (like obsidian) that was moved here, or perhaps something industrial like old slag from the local area. Any help identifying it or explaining the "dotted" layers would be greatly appreciated!