1035-1135

French scholar who wrote on the medicinal uses of herbs and even gems. Bishop of Rennes (1061-81), Marbode wrote Liber de lapidibus, which may be the same work as his De gemmarum. In any case, both were on the spiritual and medicinal properties of precious stones. Regarding the diamond, for instance, Marbode wrote, "nocturnal spirits and bad dreams it repels.... Cures insanity.... For these purposes the stone should be set in silver, armored in gold, and fastened to the left arm." Elsewhere Marbode wrote that the herb artemis could cause an abortion in a pregnant woman.