Giovanni Bernardi (1494 – 22 May 1553), also known as Giovanni da Castel Bolognese and as Giovanni da Castelbolognese, was an Italian gem engraver and medalist who was born in Castel Bolognese, Italy. He was the son of a goldsmith and by 1530 had moved to Rome. His patrons include Pope Clement VII (1523–34) and Cardinal Ippolito de' Medici (1511–35). Bernardi was best known for his intaglios engraved in rock crystal. He died in Faenza, Italy in 1553.
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