| Answer | Crossword Clue |
|---|---|
| ONYX | Black stone |
| ONYX | Jet-black stone |
| EBONITE | Hard black stone. |
| jet | hard black stone |
| jets | hard black stone |
| CAABA | Building containing Black Stone of Mecca. |
| touchstone | a highly siliceous (usu black) stone or other stone for testing gold or silver by the colour of the mark each makes on it; (fig.) a criterion, a standard |
| touchstones | TOUCHSTONE, a highly siliceous (usu black) stone or other stone for testing gold or silver by the colour of the mark each makes on it; (fig.) a criterion, a standard |
