| # | Clue | Answer As Given | Value | Round | Category | Air Date | Show |
|---|---|---|---|---|---|---|---|
| This black volcanic glass was used by the ancient Maya for mirrors | obsidian | $800 | DJ | ROCKS & MINERALS | 1994-05-25 | #2253 | |
| Black, shiny volcanic glass named for Obsius, who, Pliny said, discovered it | obsidian | $300 | J | ROCKS & MINERALS | 1987-10-08 | #709 | |
| It's the black glass produced by volcanoes | obsidian | $800 | DJ | ROCKS & MINERALS | 1985-06-05 | #193 |