| Answer | Crossword Clue |
|---|---|
| haematites | A reddish-black mineral consisting of ferric oxide. It is an important ore of iron |
| hematites | A reddish-black mineral consisting of ferric oxide. It is an important ore of iron |
| columbites | A black mineral, typically occurring as dense, tabular crystals, consisting of an oxide of iron, manganese, niobium, and tantalum. It is the chief ore of niobium |
| columbite | A black mineral, typically occurring as dense, tabular crystals, consisting of an oxide of iron, manganese, niobium, and tantalum. It is the chief ore of niobium |
| ilmenites | A black mineral consisting of iron titanium oxide, of which it is the main ore |
| ilmenite | A black mineral consisting of iron titanium oxide, of which it is the main ore |
