Cristofani is specific to central Italy, it would seem to have more stocks, in Lazio, Romagna and Lucca, Cristofano, decidedly more rare, seems typical of the Molise region on the border with Campania, should derive from the auspicious name Christhophanus. The use of the vulgar form of this name is already in vogue in Pisa in the early 1400s, where Cristofano di Gherardo di Dino, abacus master, wrote his Pratica geometriae in 1446: "... Here begins the practice of geometry of Mo Lunardo Pisano ... ". The surname Cristofani was already in use in the 1500s, when the notary Nicolao Cristofani operated in Lucca whose registers are kept in the archive of the State of Lucca.
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