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Some well known materials that exhibit easily detectable magnetic properties are [[iron]], some [[steel]]s, and the [[mineral]] [[lodestone]]; however, all materials are influenced to greater or lesser degree by the presence of a [[magnetic field]].
HISTORY
In China, the earliest literary reference to magnetism lies in a [[4th century BC]] book called ''Book of the Devil Valley Master'' (鬼谷子): "The lodestone makes [[iron]] come or it attracts it."<ref>Li Shu-hua, “Origine de la Boussole 11. Aimant et Boussole,” ''Isis'', Vol. 45, No. 2. (Jul., 1954), p.175</ref> The earliest mention of the attraction of a needle appears in a work composed between 20 and 100 AD (''Louen-heng''): "A lodestone attracts a needle."<ref>Li Shu-hua, “Origine de la Boussole 11. Aimant et Boussole,” ''Isis'', Vol. 45, No. 2. (Jul., 1954), p.176</ref> By the 12th century the Chinese were known to use the lodestone compass for navigation. Far earlier [[Magnetotactic bacteria]] had evolved to build miniature magnets inside themselves and use them to establish their orientation relative to the Earth's magnetic field [http://www.astronomycafe.net/qadir/ask/a11651.html].
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