47:12 · This is a sign for a purification process in alchemy whereby one purified a substance by heating it to white-hot, burning out all impurities. It was probably often used by the alchemists interchangeably with the sign in this group.
    According to Gessmann (Die Geheimsymbole, Berlin 1922) this signs meant calcinatio auri, the burning of gold to powder by intense heating.