Mining

4. the process of increasing in size
7. a mass of small bubbles in liquid caused by agitation,
8. the upper layer of earth in which plants grow
9. a precious shiny greyish-white metal
12. removes impurities or unwanted elements from (a substance)
14. (of resources or reserves) completely used up
15. a building equipped with machinery
16. the nature of something's ingredients or constituents
17. under surface of earth
18. a powdery substance made by calcining lime and clay
19. plants considered collectively, especially those found in a particular area or habitat

1. compress or squeeze forcefully
2. the action of restoring something that has been damaged to its former condition
3. tending to mix with, dissolve in, or be wetted by water
5. a precious silvery-white metal
6. a naturally occurring solid material
10. economic activity concerned with the processing of raw materials and manufacture of goods in factories:
11. the necessary items for a particular purpose
13. is the action of floating in a liquid or gas