|Albertus Magnus and a hermaphrodite|
from Symbola aureæ mensæ
There is, for instance, a legend that he managed to transform simple metal into gold, using the Philosopher's Stone. Supposedly, he gave the Stone to his pupil, Thomas Aquinas, prior to Magnus' death. The legend fails to take into account that Aquinas died six years before Magnus. The legend further states that Aquinas destroyed the Stone, fearing a connection with less-than-divine powers. This is recorded in a 1617 work on alchemy called Symbola aureæ mensæ [Latin: "Symbols of the golden table"], by Michael Maier. It is also said that he changed the weather of a winter day to a warm spring day with flowers blooming so that a party could be held outside.
He is also credited (supposedly according to eyewitnesses) with having created an automaton in his laboratory that could speak and perform menial tasks.
As for writings that we can firmly attribute to him, there is little there about alchemy. His De mineralibus [Latin: "Concerning minerals"] alludes to the occult power found in stones, but never explains what those powers might be. His chemical experiments seem to have led to the discovery of arsenic and silver nitrate.
His commentaries on Aristotle, and his ability to blend Aristotelian logic with Christianity, as well as his various (legitimate) experiments, gained him such a reputation for intelligence that it is not surprising that future authors would assume he achieved magical results.