If you're looking at the work of art and you want to understand what is original and what's a restoration, you will take a tiny supple of pigment and analyze it.
Today, there are about 2,500 works of art of this kind across the current and historic royal residences, where they've played a central role in luxurious palace furnishing.
Right. So some of this seems to be, you're suggesting, a kind of a cultural convention and pressure. We're told what books, what works of art are great. - Right.
More than two hundred works of art belonging to the singer George Michael, who died in 2016, will go on display today in London ahead of being auctioned next Thursday.
Years before her time, she challenged society's expectations, and was able to create Surrealist works of art that examined the inner workings of the human soul.