Researchers Dr. Anne Bailey and Dr. Richard Thomas analyzed the artwork techniques used in Renaissance frescoes. They observed that while most frescoes were painted on plaster mixed from local lime, the pigments used for detailing and highlights were often imported from distant regions. They concluded that Renaissance artists deliberately chose these special pigments for their vividness and quality, even though it required importing them from afar.
Which finding, if true, would most strongly support the researchers’ conclusion?