B lue, the colour of skies and oceans, is a desirable and alluring hue that has appeared in art since the dawn of history. Often symbolically linked to bravery, truth and unity, blue has been shown to have physical effects including lowering heart rate and enhancing memory. So important is blue and its associations to emotions that it is the colour of choice by American author Maggie Nelson who sets out to explore love, loss and solitude through a lyrical and philosophical meditation of the colour in Bluets.
'Blue colour is everlastingly appointed by the deity to be a source of delight.'
On the occasion of The Infinite Blue, a single-lot auction of a rare 11.28-carat Fancy Vivid blue diamond ring presented by Sotheby’s Hong Kong this October, we dive deep into the history of a colour that has captivated artists, emperors, empresses, kings and queens for centuries. Blue diamonds are among the most coveted and rare – only 0.1% of the total mining production can produce blue diamonds, irrespective of the strength of colour. Yet the power and allure of this colour transcends the realm of high jewellery; it is woven into the very fabric of artistic expression and world culture.
The ancient Egyptians, who saw blue as the colour of the heavens, used azurite and lapis lazuli – imported from Afghanistan across the Sinai Desert at great cost – to create blue jewellery and pigments. During the Fourth Dynasty of the Old Kingdom (c. 2613 to 2494 BC) the Egyptians invented the first synthetic blue dye: Egyptian Blue (calcium copper silicate). The Minoans, the citizens of ancient Crete, imported Egyptian Blue and used it as a pigment in their colourful murals depicting dolphins and sea life. The Egyptians also developed faience, a sintered quartz ceramic material, which appeared in a variety of blue and turquoise hues. Blue faience hippos, symbolising fertility and rebirth, have been found in the tombs of ancient Egyptian high officials.
Meanwhile, the Romans had two terms for blue: caesis for sky blue and caerulis for deep sea blue. They relied on Egyptian Blue for murals and decorations and also developed a fabric dye made from woad, a yellow flowering plant from Brassicaceae, the mustard family. Many common Roman glass vessels were aqua (pale blue-green) in colour, because of their iron oxide content. Additionally, blue was used as the colour of mourning and also associated with Barbarians (Celts and Germans) who were known to dye their faces blue to frighten their enemies in battle.
In China, blue ceramics – including jars dipped or splashed with blue cobalt glaze – appeared during the Tang dynasty (618-907). During the later Mongol-ruled Yuan Dynasty (1279-1368) richer and more complex decorations appeared, evolving towards the refined blue and white decorated porcelain favoured by the Imperial court and used as gifts by diplomats. Beginning in the Ming dynasty (1368-1644) locally mined cobalt, including shi qing (mineral blue) from the Jiangxi province would be mixed with cobalt imported from Persia – which was scarce and only used in limited quantities – allowing for a greater vareity of tones and effects and greater accessibility. By the end of the 16th century blue and white export pottery – often decorated with mythological and real animals, flowers and landscapes – had become a popular trade item all across Europe.
During the early Italian Renaissance the Virgin Mary, cloaked in blue, became a central subject of religious art. Laws were passed to ban ordinary citizens from wearing blue, reserving it exclusively for depictions of the Virgin. “A noble colour, beautiful, the most perfect of all colours,” wrote the artist Cennino Cennini (1360-1427). The supply of Ultramarine blue pigment, made from the finest imported lapis lazuli, was controlled by the church which resulted in it becoming more expensive than gold. When the Scrovegni Chapel in Padua, decorated with lifelike frescoes by Giotto (1267-1337) under an Ultramarine ceiling pierced by gold stars, was unveiled in 1305 its lavish use of blue dazzled worshippers. Around the same period, visitors to Chartres Cathedral in France would have been welcomed by nearly an acre of luminous stained glass, much of it tinted "Chartres Blue" by hues of cobalt. During the 17th century Dutch painter Johannes Vermeer (1632-1675) used a particularly choice shade of lapis lazuli-based Ultramarine – a deep blue with the slightest hint of green – called Cornflower Blue, a hue that is also found in the finest sapphires, including Kashmir sapphires, which have been described to possess a “soft and velvety” blue.
In the centuries that followed, blue, once the colour of royalty, became more varied and affordable. In Japan, Indigo blue – an expensive dye made from the Indigofera Tinctoria plant and used for thousands of years in India, East Asia and Egypt – exploded in popularity during the Edo period (1603-1868). Because commoners were banned from wearing silk, cotton clothing, which was easily dyed with indigo, became widely popular and the dye fell in price. Synthetic indigo, developed in Europe at the end of the 19th century, is the colour of today’s blue denim. The accidental discovery of Prussian Blue in Germany in 1704 provided 18th century Romantic painters and Edo period Japanese printmakers with an affordable deep blue that offered rich new tonalities. Cerulean Blue, first synthesised in 1805, is a pale azure that rapidly became essential for landscape painters including the French Impressionists.
As the varieties of blue pigment increased, artists combined them for artistic effect. Gainsborough’s famous "Blue Boy" of 1770 wears a blue satin outfit that was rendered with indigo, lapis lazuli and cobalt pigments. Picasso’s "Blue Period" portraits relied heavily on Prussian Blue but also included newer synthetic Ultramarine pigments. The artist Yves Klein (1928-1962) who as a teenager had "claimed" the sky, worked with a paint dealer in Paris to develop his singular shade of Ultramarine in 1960, dubbed International Klein Blue. Working with nude female models – "living brushes" coated in his signature colour – he painted in front of live audiences, creating a new form of art that married painting and performance.
'Blue has no dimensions, it is beyond dimensions, whereas the other colours are not.'
Today blue is available to artists in a wide range of synthetic, organic and mineral pigments: the Winsor & Newton company offers oil painters 15 hues to choose from. Chemists have come up with synthetic Ultramarines that closely imitate the brilliance of lapis lazuli, and others that can substitute for Manganese Blue, once used to colour swimming pools but now banned due to its toxicity. A 2015 study conducted across four continents asked people to name their favorite colour and confirmed that blue is the most popular colour in the world. As popular as it now is, blue can still be said to be the colour of royalty. Elvis Presley – whose fans called him "The King" – once performed in Las Vegas wearing a chunky gold ring set with a cabochon-cut blue lapis lazuli stone as brilliant as the sky of the Scrovegni Chapel.