Lodestone is a naturally magnetic form of the mineral magnetite (iron oxide). Magnetite from all known localities can be picked up by a magnet,but only the rare kind that itself projects magnetic attraction can be called lodestone. Use of this material was undoubtedly the first method ancient civilizations had for creating the compass,leading to global navigation and the spread of civilization. Magnetite is widespread and abundant on earth and even occurs in meteorites,but the material that exhibits intrinsic polarity is quite rare. One well-known locality is at Magnet Cove,Arkansas | |
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