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Frequently Asked Questions

A naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties.

A rock is an aggregate of one or more minerals; or a body of undifferentiated mineral matter.

EarthWord–Rock vs. Mineral

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.

  • A telephone contains over 40 different mineral materials, a television set has about 35, and an automobile about 15.
  • Of the approximately 193,000 metric tons of gold discovered, 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 approximately 1,740,000 metric tons of silver discovered, 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.
  • At today's level of consumption, the average newborn infant will need a lifetime supply of 886 pounds of lead, 552 pounds of zinc, 945 pounds of copper, 21,276 pounds of iron, 11,977 pounds of clays, 37,587 pounds of salt, and 1.31 million pounds of stone, sand, gravel, and 72,994 pounds of cement. (figures from Minerals Education Coalition)
  • What is the meaning of the karat mark (K) on gold jewelry? The fineness of jewelry gold is stated as the number of parts in twenty-four that are gold. Thus, 24 karat gold is pure gold; 12 karat would be an alloy that is half gold and half copper or other metals.
  • Fool's Gold can be one of three minerals; the most common mineral mistaken for gold is pyrite, chalcopyrite may also appear gold-like, and weathered biotite mica can mimic flake gold.
    The Golden Rule on April Fools

Related Links

copper specimen
A sample of native copper. Photograph credit: USGS.

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