Solve the crossword "NATURAL WORLD"

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Across
  1. 6. Very beautiful or pleasant
  2. 7. Features belonging to the culture of a particular society, such as traditions, languages, or buildings, that were created in the past and still have historical importance
  3. 10. To keep something as it is, especially in order to prevent it from decaying or being damaged or destroyed
  4. 12. A line of mountains connected
  5. 14. A hard black mineral that is found below the ground and burnt to produce heat
  6. 15. A forest with tall trees with long, thin leaves shaped like needles
  7. 17. Something very valuable
  8. 18. An area of low land between hills or mountains
Down
  1. 1. Different from one another
  2. 2. A large mass of ice, formed by snow on mountains
  3. 3. To separate two different regions
  4. 4. Plants in general
  5. 5. Short trees
  6. 8. About, almost
  7. 9. A carving or drawing on rock, especially one made by prehistoric people
  8. 11. Important or noticeable
  9. 13. Grassland
  10. 16. Rock or earth from which metal can be obtained