Lodestone was historically used for compasses-it's a natural magnetic substance.
From the en.wikipedia.org
Only a small amount of the magnetite on Earth is found magnetized as lodestone.
From the en.wikipedia.org
The first compasses were made of lodestone, a naturally-magnetized ore of iron.
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A lodestone or loadstone is a naturally magnetized piece of the mineral magnetite.
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The process by which lodestone is created has long been an open question in geology.
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The lodestone compass was used for navigation in medieval China by the 12th century.
From the en.wikipedia.org
If a needle is rubbed on a lodestone or other magnet, the needle becomes magnetized.
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To save their trade and their ships, the Portuguese took away the lodestone.
From the en.wikipedia.org
New York is a lodestone to the literary talent of the entire United States.
From the theatlantic.com
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A permanent magnet consisting of magnetite that possess polarity and has the power to attract as well as to be attracted magnetically
A lodestone or loadstone is a naturally magnetized piece of the mineral magnetite. They are naturally occurring magnets, that attract pieces of iron. Ancient people first discovered the property of magnetism in lodestone. ...
Lodestone is a Marvel Comics supervillain who first appears in Darkhawk #7.
(From the old English, "lad" [leader or guide], thus the guiding stone for mariners.) It is a magnetized piece of iron ore that can impart its north-south properties to an iron needle. This needle was then used to make a compass.
A magnetic stone used as a crude compass. Slivers of lodestone, suspended from a cord, or floated atop a small piece of wood in a water jar, seek magnetic north. The lodestone is most commonly used by less technically seaman. Also see: Compass.
A precious stone believed to possess magical properties of diverse kinds. If one is ill, one must hold it in one's hands and shake it well. It cures wounds, snake-bites, weak eyes, headaches and restores hearing. ...