pitchstone
/ˈpɪtʃˌstoʊn/
noun
- A dark, glassy volcanic rock that looks like hardened pitch or tar.
- Geologists found a large deposit of pitchstone near the ancient volcano.
- Pitchstone is sometimes used in jewelry because of its shiny, dark surface.
- The hiker picked up a piece of pitchstone that glistened like black glass.