lavaglass
nounUK /ˈlɑːvəɡlɑːs/
US /ˈlɑːvəɡlæs/
Lavaglass is a shiny, dark glass made when hot lava cools very fast.
The beach was covered with bits of black lavaglass that sparkled in the sun.
OTHER MEANINGS
2. A decorative material made by melting rock and shaping it into glass-like pieces.
She wore a necklace made of polished lavaglass.
3. A type of jewelry stone formed from cooled volcanic rock.
The bracelet had round beads of lavaglass.
4. A glassy crust that forms on the surface of a lava flow.
Scientists studied the lavaglass on the cooled flow.