Turner's paintbox

In the midst of an art-filled day, the girls and I visited the Making Colour exhibition at the National this afternoon. It was a fascinating foray into the origins and significance of paint pigments used in art.

For years I've thought that galleries should provide contextual information for paintings; why they're painted in a certain way or use particular colours and the technical processes involved in bringing paintings to life.

To me this context adds an extra layer of understanding and therefore appreciation of what it takes to create art. I suppose it means I admire the technical/craft skill behind painting as much as the conceptual talent.

Because of the subject matter the exhibition brought together a great cross section of paintings by different artists from different eras. As we walked round the exhibition Alice sat on the floor (each room dealt with a different colour) and wrote notes about the origins of paint colours, in her suction notepad.

So...

Did you know that ultramarine is produced from the mineral lapis lazuli which has to be mined under hazardous conditions in a remote part of Afghanistan. Ultramarine was reserved for only the best commissions and its presence in a painting indicated great wealth. It still produces the best blue of all.

Bright yellow pigment was not created and is therefore not seen in paintings until the 16th century. Meanwhile realgar, a mineral used to create bright orange paint and used by artists such as Titian, contains arsenic and is extremely poisonous.

Silver is scarce in paintings because it's unstable and deteriorates, unlike gold. Giovanni Girolamo Savoldo's painting of Mary Magdalene wearing a shimmering silver cloak in fact contains no real silver. Instead her cloak was painted entirely using cheap black and white paints. The result is sublime.

I'm quite overwhelmed sometimes when I look at great paintings like this because I just can't conceive how someone can actually create something so beautiful using just paint, brush and canvas. How do they begin to do that? To me it's absolutely magical.

My top exhibition highlight amid the paintings was Turner's paintbox, found in his studio after he died. It still holds little pigs bladder packages containing ready-mixed paint as well as glass vials of pure, precious pigment waiting to be mixed for Turner's next masterpiece. Amazing.