| Answer | Crossword Clue |
|---|---|
| FOOLSGOLD | Iron sulfide with a deceiving color |
| stannite | mineral, iron-black to steel-gray in color, with a metallic luster, copper iron tin sulfide, Cu2FeSnS4: an ore of tin |
| bornites | common mineral and important ore of copper, copper iron sulfide, Cu5FeS4, occurring in masses, of brownish color when first exposed to the air; peacock ore |
| bornitic | common mineral and important ore of copper, copper iron sulfide, Cu5FeS4, occurring in masses, of brownish color when first exposed to the air; peacock ore |
| bornite | common mineral and important ore of copper, copper iron sulfide, Cu5FeS4, occurring in masses, of brownish color when first exposed to the air; peacock ore |
