Sistine Chapel ceiling of the Sistine Chapel. At the outset, the plaster, "intonaco", began to grow mold because it was too wet. Michelangelo had to remove it and start again. He then tried a new formula created by one of his assistants, Jacopo l'Indaco, which resisted mold and entered the Italian building tradition. Because he was painting "fresco", the plaster was laid in a new section every day, called a "giornata". At the beginning of each session, the edges would be scraped away and a new area laid down. The edges between "giornate" remain slightly visible; thus, they give a good idea of
Restoration of the Sistine Chapel frescoes out of the gloom above the lunette of Jesse. Arguimbau says: Richard Serrin, in an essay entitled "Lies and Misdemeanors: Gianluigi Colalucci's Sistine Chapel Revisited" says: Carlo Pietrangeli, former Director General of the Vatican Museums, writes of the restoration: "It is like opening a window in a dark room and seeing it flooded with light." His words resonate with those of Giorgio Vasari who, in the 16th century, said of the Sistine Chapel ceiling: Pietrangeli, in his foreword to "The Sistine Chapel", written after the restoration of the lunettes, but prior to the restoration of the ceiling, commends those who