| Answer | Crossword Clue |
|---|---|
| perlitic | pertaining to perlite (a volcanic glass) |
| perlites | PERLITE, a volcanic glass |
| obsidians | volcanic glass similar in composition to granite, usually dark but transparent in thin pieces, and having a good conchoidal fracture |
| obsidian | volcanic glass similar in composition to granite, usually dark but transparent in thin pieces, and having a good conchoidal fracture |
| taxitic | pertaining to taxite (a volcanic rock) |
| vesuvian | volcanic, or pertaining to a fierce or fiery disposition. |
| lithic | pertaining to clastic rocks, either sedimentary or volcanic, containing a large proportion of debris from previously formed rocks |
