Although the Arab chronicler al-Bakri was told by some that asbestos came from a tree, those who knew more told him it came from a mineral in the ground:

Among the strange things found in the land of the Sudan is a tree called TWRZY which has a long thin trunk and grows in the sands. It has a big, puffed-up fruit containing white wool from which cloth and garments are made. Fire cannot damage the materials made of this wool, however long they are exposed to it. The jurist 'Abd al-Malik relates that the people of al-Lamis (a place in those parts) wear only clothes of this kind. Stone with similar characteristics is found in the Dar'a valley and called in the Berber language tamatghust. When rubbed in the hand it becomes so soft that it takes on the...