“What is blue? Blue is the invisible that turns visible.” Yves Klein.
As a Nature lover I have always considered Blue and Green two colours related, not only due the fact they are analogous-adjacent in the colour wheel, but because Blue is the Cosmos and Green is the Nature.
Blue is the symbolic colour of eternity, of harmony, it’s deep and immaterial, in nature it’s found only as transparency, made of emptiness-air-water, which dematerializes all that is wrapped in it, which undoes the boundaries, dissolves the forms. Entering the blue is equivalent to passing on the other side of the mirror, where the real is transformed into imaginary. It’s a feminine colour, uranic, of the Celestial Dome, symbol of high status.
Green gives a sense of stability, hope. More dark Blue is added more solid and authoritative results. It is equidistant from the Celestial Blue and from the Infernal Red, both absolute and inaccessible. It’s the colour of immortality, of life, of the regenerating vegetable kingdom, the refuge in the maternal world, of the awakening of primordial waters as an ocean of origins.
“I wouldn’t build a house for myself but if I had to, I would, like some Romans, build it right into the sea. I certainly would like to share a few secrets with this beautiful monster.” Nietzsche.
In ancient times many Blue and Green colours were obtained from Nature, from Minerals and Plants, the only sources available.
Egyptian culture created the Egyptian Blue, a stable silicate of Calcium and Copper. Smalt is another Blue used among the Egyptians. And it’s the first form of Cobalt found in history too. It’s made from Blue Glass, affordable, and widely used during Renaissance. Replaced by the synthetic form in 1804 by chemist Thénard. Cobalts have an excellent lightfastness, are semi-transparent, good for mixing, but are very expensive. The range goes from Violet-Blue-Green-Turquoise Teal to Yellow.
From semi-precious stones was extracted Lapislazzuli and Turquoise.
Turquoise is made by Hydrous Phosphate of Copper and Aluminium, a light bluish Green.
Lapislazzuli (literally “beyond the sea”, because imported in Europe from Asia) is renowned as the most precious and expensive Blue pigment of all times, even more than Gold. It comes from Afghanistan, it was found since 6th century. Since Medieval and Renaissance period it was used for sacred paintings and manuscripts, especially for Madonna’s mantle, generally Blue. Obviously over the time this pigment has become increasingly unobtainable due to the exhaustion of the mines. This colour has a marvelous Purple shade, excellent lightfastness, and impurities of Pyrite make it bright. The synthetic and cheaper form Ultramarine was developed only in 1826 from French chemist Guimet. When chemically modified it produces Ultramarine Violet in Red-Blue hues.
Azurite is similar to the costly Lapislazzuli, but cheaper. It’s made by Copper, even if it tends to change colour to a sort of green like Malachite, and even more dark.
Malachite, from Copper’s Carbonate too, known also as Mineral Green or Verdeazzuro, is the oldest Green of history, but absolutely not lightfast.
In Middle Ages was used Verdigris, a vibrant bluish Green colour made from Copper (again!). It tends to darken and degrades surfaces. Also named as Spanish Green, better not mixing with White Lead. Cennini in his Book of Art mentioned this colour at the time.
Green Earth (PG23) is also named as Verona Green, Stone Green, Verdetta, Bohemian Green. Made from minerals such as Glauconite and Celadonite, is a mixture of Iron-Magnesium clays, a transparent colour, with a range from Yellow to Grey. Very used during Medieval and Renaissance period, especially as underpainting colour for flesh tones in portraits.
Some organic Blue are extracted instead from plants: Indigo from Indigofera Tinctoria and Woad from Isatis Tinctoria. They were introduced in Europe during 17th century, but their use is known since antiquity. The synthetic form was introduced only in 1870.
One of the first Blue used was Mayan Blue, it has been found on pottery and artifacts of Mayan and Aztec civilizations. It’s a mixture of clays and Indigo, very stable, even if the recipe is still unknown.
In Medieval times Iris Green was obtained from the juice extracted from the Blue Purple petals of Iris. Obviously it was necessary a lot of flowers to obtain this pigment. It was often used in manuscripts.
From the berries of the Buckthorn is made Sap Green, a fugitive lake made from the juice of this plant, with a rich Yellow undertone.
And talking about flowers and botany, a few words on Hookers Green. It took the name from Victorian botanist Sir Joseph Dalton Hooker, director of the Kew Gardens in London and President of the Royal Society. He made a mixture of Prussian Blue and Genuine Gamboge Yellow to create this colour.
Prussian Blue (PB27) has a singular story behind its origin. It’s the first synthetic pigment obtained by mistake in 1704 by Diesbach while trying to create a Red Lake. Despite its content (Ferrous Ferrocyanide Salts) it isn’t extremely toxic, infact it’s used as antidote for heavy metal poisoning. Also named as Berlin Blue, Parisian Blue, Chinese Blue, Steel Blue, Milori Blue. It tends to fade in the light, but returns to its original colour when in the dark.
Anyway, as soon as I’ll finish these posts about colours, I’ll made one about my world favorite gardens.
To be continued…