Magnetic susceptibility of
natural rocks and ores is important in many applications. In a few rock types
magnetic susceptibility is independent of the direction in which a weak
magnetic field is applied. Such rocks are magnetically isotropic. In most rock
types, however, the magnitude of magnetic susceptibility in a constant weak
field depends on the orientation of the magnetic field applied. Such rocks are
magnetically anisotropic and such directional variation in magnetic susceptibility
with these rocks is termed as anisotropy of magnetic susceptibility (AMS).
Although attempts have been made on describing AMS using mathematical models,
there is still a need to present a more consistent and united mathematical
process for AMS. This paper presents a united AMS model by rationalizing the
existing pieces of different AMS models through a consistent approach. A few
examples of AMS from some types of natural rocks and ores are also presented to
substantiate this united AMS model.
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