how is quartz formed in the earth’s crust?\n a. through precipitation from water\n b. through alteration of…

how is quartz formed in the earth’s crust?\n a. through precipitation from water\n b. through alteration of existing minerals\n c. through volcanic activity\n d. through the crystallization of silicon dioxide molecules\n\nwhich mining technique uses gravity separation to extract minerals from riverbeds?\n a. cyanide leaching\n b. underground mining\n c. surface mining\n d. placer mining

how is quartz formed in the earth’s crust?\n a. through precipitation from water\n b. through alteration of existing minerals\n c. through volcanic activity\n d. through the crystallization of silicon dioxide molecules\n\nwhich mining technique uses gravity separation to extract minerals from riverbeds?\n a. cyanide leaching\n b. underground mining\n c. surface mining\n d. placer mining

Answer

Brief Explanations:

Quartz is a mineral composed of silicon and oxygen atoms. It forms through the crystallization of silicon - dioxide molecules. Placer mining uses gravity separation to extract minerals from riverbeds as heavier minerals settle due to gravity.

Answer:

  1. d. Through the crystallization of silicon dioxide molecules
  2. d. Placer mining