Janus Lacinius [Therapus] (Giano Lacinio) was, as he and the various liminary verses proudly proclaim (those by Hippolytus Fantotius of Perugia, written as if the 'Ars divina' is speaking give both his forenames), a native of Calabria from Psychronea, and a minorite friar, i.e. a Franciscan. Sbaralea (SupplEad scriptorum trium ordinum s. Francisci, II, Rome, 1921 p. 22) treats the name as a pseudonym and identifies him with John of Croton, from a promontary in Calabria called Lacinium. The Pretiosa Margarita novella circulated in manuscript and is attributed generally to one Petrus Bonus (Pietro Bono, see article by C. Vasoli in DBI 12 pp. 287-289), who in turn refers to many earlier alchemical sources. It is interesting not only for its alchemical content, and the practicalities of alchemy, but also for the light it throws generally on fourteenth-century technology. It is (as Vasoli remarks) distinguished 'for the noteworthy simplicity of the procedures proposed and by nature of being a practical manual, written for a public of 'scientists' and scholastic academics'.