From The Iris (Getty Museum – April 17, 2020):
To work out the details of all the figures in pen and ink would have been extremely labor-intensive, and sharpening quills and mixing inks would’ve added an additional distraction. Drawing in chalk necessitated great skill, but it also allowed Michelangelo a flexibility. He could create subtle tonal variations by applying more or less pressure onto the chalk or by wetting it. The red chalk also provided an immediate mid-tone on the paper and could be easily blended when modeling and shading forms. Being a naturally occurring material that was available to artists in sticks that could be sharpened as desired, it was also convenient and portable.
During his lifetime, Michelangelo likely produced tens of thousands of drawings. But being protective of his ideas, and to give an impression of effortless genius, he destroyed many of them. Today only about 600 drawings by the Renaissance artist survive. A Getty exhibition highlighted 28 of them, giving viewers a window into Michelangelo’s artistic process. “He used drawings to record his observations, to explore certain ideas, to further develop these ideas, to reconsider them entirely,” said Assistant Curator Edina Adam.
The exhibition included a relatively high number of drawings in red chalk, which prompted the question: Why did Michelangelo use this particular drawing material?
Minton had gone on to produce a series of spectacularly colourful oil paintings of Corsica on his return to London, exhibiting them at the Lefevre Gallery in 1949. Many of them depicted fruit and fish and other ingredients for Mediterranean cuisine, and so confirmed Minton as the obvious choice for the David commission. 
year. Directed by Cosima Spender, this film maps the roots of Barlow’s oeuvre, as she revisits childhood memories, domestic and urban spaces, and their subsequent role in her creative process. 
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