Across
- 3. once used it's gone
- 6. hard rock another form of lignite
- 7. used for heating and cooking
- 8. taking back a resource and using it to make a new product
- 10. natural resource that can be used more than once
Down
- 1. soft brown rock that covers peat
- 2. remains of once living organisms
- 4. can be used more than once
- 5. materials people take from earth
- 9. soft brown material made from dead plants
- 11. black rock almost pure carbon