Minerals must be mined from the ground, either by surface, underground, or drilling methods. Sand and gravel is usually mined in surface pits or rock is crushed to size, gold is mined in surface pits, underground mines, and in streams and rivers.
At today's level of consumption, the average newborn infant will need a lifetime supply of 800 pounds of lead, 750 pounds of zinc, 1,500 pounds of copper, 3,593 pounds of aluminum, 32,700 pounds of iron, 26,550 pounds of clays, 28,213 pounds of salt, and...
To maintain our standard of living, each person in the United States requires over 48,000 pounds of minerals each year: 12,528 lb. of stone 9,385 lb. of sand and gravel 888 lb. of cement 280 lb. of clays 418 lb. of salt 309 lb....
Of the 1.52 billion metric tons of copper discovered to date, 56% is found in just four countries on earth. All the copper discovered thus far would fit in a cube 550 meters on a side.
Of the 193,000 metric tons of gold discovered to date, 62% is found in just four countries on earth. All the gold discovered thus far would fit in a cube 22 meters on a side.
Of the 1,740,000 metric tons of silver discovered to date, 55% is found in just four countries on earth. All the silver discovered thus far would fit in a cube 55 meters on a side.
Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot, mineral...
A naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties.
Gneiss is a coarse-grained, foliated metamorphic rock that commonly has alternating bands of light and dark-colored minerals.
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