Reader question: “I’m wondering about cobalt and the story about blue colours being so expensive in the past – is that true and does it have any importance for the evolution of art?”
It is true! But it’s actually not cobalt blue that you’re thinking of, it’s ultramarine.
The history of colours in art is really weird and interesting. It’s true that the availability of various colours has often determined which ones are used and what importance they have. This is especially true the further back we go in history, when all colours were not readily available in the nearest art shop.
A surprising variety of methods were used to make different colours. To make bright red, for example, an early 8th century process was described by Persian alchemist Jabir ibn Hayyan: you had to heat mercury and sulfur in a flask, vaporize and recondense it, and then grind it to create a red colour.
Some colours were very cheap and easy to make and where therefore used often. Yellow and red ochre are really common and have been used in art ever since Paleolithic cave paintings. You can also see them everywhere in Ancient Egyptian tombs. In Roman painting, yellow and red ochre were regularly used in frescoes and paintings, and the hues vary slightly depending on the colour of the local clay.
Ultramarine blue (not cobalt blue) is maybe the most famous expensive and rare colour pigment. It was made by grinding Lapis Lazuli stones into a powder, and was one of the most difficult stones to grind by hand. Lapis Lazuli comes mainly from Afghanistan and Pakistan and had been exported to the Mediterranean world, Egypt and South Asia for thousands of years before it came to Europe. It usually held great significance; Cleopatra, for example, apparently used powdered lapis as her eye shadow.
The stone began being exported to Europe in the Middle Ages, where it was ground into a pigment known as ultramarine. Because it was so rare and difficult to get, ultramarine became the finest and most expensive colour that could be used by Renaissance artists (Italian artists from the 13th to the 15th century). A Renaissance artist called Cennino Cennini in the 15th century described ultramarine as “a color illustrious, beautiful, the most perfect, beyond all other colors; one could not say anything about it, or do anything with it, that its quality would not still surpass.” Because it was so special and amazing, it was often used for paintings of the Virgin Mary and was used by the very best painters.
Ultramarine continued to be used in Europe in the 17th and 18th centuries, most famously by Johannes Vermeer. In the 19th century, cobalt blue – which had been used for ages in Chinese porcelain – was discovered as an alternative to ultramarine in France. In 1826 a synthetic version of ultramarine was invented.
Today we can get virtually any colour we want and no colour is more difficult to get than the other. That means that it’s hard for us to imagine what, for example, a viewer from Renaissance Italy would think when they looked at a painting of the Virgin Mary with an ultramarine robe.
It’s important to remember that the physical limitations of painting throughout history often affect how we should interpret and read the resulting artworks.