Which one of techniques below was not used by ghiberti in his panel the story of jacob and esau (15.17) from the gates of paradise (east doors) of the baptistery of san giovanni?

The technique Ghilberti used is Fresco. Ghiberti is a standout amongst the most vital early Renaissance stone carvers, Ghiberti is best known as the maker of the bronze entryways of the Baptistery of Florence. 
Lorenzo di Cione Ghiberti was conceived in Pelago, close Florence, Italy, in 1378. He was all around prepared by his dad, Bartoluccio Ghiberti, a very much regarded goldsmith in Florence. In 1392, he was admitted to the "Silk and Gold" Guild as an understudy, and by 1398, had passed his examination to wind up plainly a society ace goldsmith. In 1400, he ventured out to Rimini to get away from the torment in Florence and got further preparing as a painter, aiding the consummation of divider frescoes at the Castle of Carlo I Malatesta.

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