Question: Mining companies conduct mineral exploration to

Answer: Find mineral deposits

Question: Airplanes used in mineral exploration carry instruments that detect what?

Answer: Gravity, radioactivity, and magnetism

Question: What is ore grade?

Answer: The metal content of an ore

Question: How is a mineral deposit different from ordinary rocks

Answer: A mineral deposit has 100 to 1,000 times the concentration of the mineral than ordinary rocks have.

Question: How do both satellites and airplanes aid mining companies in finding ore deposits?

Answer: Satellite images are used, along with photographs and data collected from planes, to create an accurate geological map of the surface.

Question: What do mining companies learn from rock samples taken from an exploration area?

Answer: They learn the ore grade, or how much metal is in the rock.

Question: How does drilling test holes help mining companies determine whether to open a mine in a specific area?

Answer: The test holes help the company estimate the three-dimensional extent of the ore.

Question: The value of a mineral is determined by its

Answer: properties

Question: What types of minerals are among the most widely used in the world?

Answer: alloys

Question: An example of gemstone?

Answer: sapphire