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prospecting, search for mineral deposits suitable for mining. Modern prospecting has replaced earlier methods based on chance or superstition (e.g., use of the divining rod) with others based on a scientific knowledge of modern geology and mineralogy. Surface indications of deposits are confirmed by extensive sampling, e.g., by examination and analysis of material taken from holes drilled at regular intervals. Modern geophysical methods of prospecting use instruments that measure variations in the earth's magnetic or gravitational field, or in the direction, nature, and velocity of waves set up in the ground by underground explosions. Electrical methods employ instruments that indicate relative electrical conductivity between points in the earth's surface or electromotive forces generated by large ore bodies. Geochemical prospecting involves the chemical or spectrographic analysis of soil, plant, and water samples. Scintillometers or Geiger counters are used to locate radioactive materials. A portable radioactive source is the basis of the berylometer, useful in locating beryl. Some minerals fluoresce in the presence of ultraviolet light; they are sought in the dark with portable ultraviolet lamps. Aerial and satellite photography and airborne instruments have proved useful for preliminary prospecting in unexplored territories.

See J. B. Chaussier and J. Morer, Mineral Prospecting Manual (1986); M. Kuzvart and M. Bohmer, Prospecting and Exploration of Mineral Deposits (2d ed. 1986).