| Answer | Crossword Clue |
|---|---|
| MINERAL | Coal or quartz |
| MINERAL | Quartz or feldspar |
| SILICATE | Quartz or mica |
| SILICATE | Mica or quartz |
| SILICA | Sand or quartz |
| MINERAL | Diamond or quartz. |
| SILICA | Quartz or flint |
| SILEX | Finely ground quartz or flint |
| SILICA | Stuff in sand or quartz |
| SILEX | Mineral in the form of quartz or flint |
