The outlet reports he's made 2 million pounds — that's close to $3 million — since 1997 off copies of his watercolors. And he donates the earnings to his charitable foundation.
See images of the prince and his work:
The estimate is based on documents from the residence of the Prince of Wales and The Duchess of Cornwall.
And an art dealer who handled his work before then told The Telegraph she estimates lithographs of his work have made closer to 6 million pounds including previous sales — or around $8.75 million.
According to the "interests" section of his website, Prince Charles has enjoyed painting for most of his adulthood.
And from time to time, he even invites young talent to paint with him.
See more of Prince Charles and Camilla, Duchess of Cornwall through the years:
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