Between 1678 and 1680 Borri aka "Giustiniani Bono", collaborated with Athanasius Kircher for construction of Porta Alchemica in Palombara villa. Gian Lorenzo Bernini, famous architect and Kircher friend, designed the door. On the door was transcribed the secret formula for producing gold discovery in those years in alchemical laboratory of queen Christina. Because of this revelation the Marquis Palombara, Bernini and Athanasius Kircher were murdered by poison at 28 November 1680, probably by the same Borri. The secret of the Philosopher's Stone was lost forever, or perhaps continued to be used by Borri. (It's amazing the similarity between portraits of Borri and the mysterious Count of St. Germain).