Lapis Lazuli: How the World's Most Precious Blue Pigment Became Ultramarine

Lapis lazuli is the semi-precious stone from which the pigment ultramarine is made.  The relationship works like this – the mineral Lapis lazuli contains lazurite.  There is evidence that it was mined in the mountains of Afghanistan as long ago as the 7570 BC. For centuries, artists ground lapis lazuli into powder and then used an elaborate purification process to separate the blue lazurite from the other minerals. The resulting pigment - natural ultramarine was one of the most expensive pigments ever used and often cost more than gold, and appeared in many paintings of the renaissance, notably to form the gorgeous blue of the robes of the Virgin Mary.

This video explores the history, science and artistic importance of lapis lazuli, the rare blue stone used to create the pigment natural ultramarine. The presenter visits artist and historian David Margus, who demonstrates how the stone is transformed into pigment by crushing it into a fine powder. As the rock is broken apart, the sulphur within it becomes apparent, and we learn that its unusual chemistry is responsible for the brilliant blue colour.  I wanted a valuation of the great lump of Lapis lazuli featured in the video but, alas, that was not forthcoming.  Regardless, this is very interesting!