Saint Jerome Reading by Vivarini, Alvise

Saint Jerome Reading by Alvise Vivarini, painted around 1476, is a masterclass in quiet luxury, the blue robe draping the saint cost more than anything else in the picture.

Look at that blue. In the late 1400s, ultramarine pigment was made from lapis lazuli mined in what is now Afghanistan, shipped to Venice at staggering expense, and ground by hand. Contracts between patrons and painters often specified exactly how much ultramarine would be used, and where. This robe is the patron's money made visible.

Now look at those hands, every vein, every knuckle rendered in egg tempera on panel. Tempera dries fast and does not blend easily, so every line is a deliberate stroke with a tiny brush. Vivarini belonged to a Venetian dynasty of painters: his father was Antonio Vivarini, his uncle Bartolomeo. Alvise became the city's leading artist before Giovanni Bellini overtook him, and this panel shows why he held that spot.

This is a painting that rewards close looking, the dead tree on the right, the pale distant water, the lapis sky, but the story is in the blue. What is the most expensive-looking color you have ever noticed in a painting?