Bezoar is a red stone, which is suppose to be precious in possessing magical properties, and is found in bodies of certain animals.
Once these stones fetched ten times their weight in gold, being used as a remedy against poison and contagion; and for this purpose they were both taken internally and worn about the neck. It is said that there are nine varieties of bezoar, differing greatly in composition; but they may be generally divided into those that mainly consist of mineral and those that consist of organic matter.
Early naturalists assigned a strange origin to this stone. It is said that the oriental stags when oppressed with years fed upon serpents, which renewed their youth.
In order to counteract the poison that was absorbed into their system, they plunged into a running stream keeping their heads above water. This caused the viscous fluid to be distilled from their eyes, which was solidified by the heat and sun, and formed the bezoar. A.G.H.
Source: 81, 68.