Red and purple
Red pigment is obtained due to high iron oxide red earth. For thousands of years, a bright red dye has been extracted from cochineal: to obtain 100 grams of pigment, about 14 thousand of these frayed insects were needed. They were collected from grass of a certain species or from a cactus.
With great difficulty, a purple dye was also obtained. It was obtained from the glands of the murex mollusk: for the sake of 100 grams of purple 100 thousand mollusks parted with life. Curiously, for humans, red is a danger sign, while most animals do not distinguish it at all. Birds are well seen in the red spectrum and, perhaps, therefore, flock to red fruits.Another source of raw material for red paint is madder grass. It has been used from antiquity to this day.
Previously, there were only two methods known to produce pure blue. You could either pour urine on the leaves of the weida dye (blue) and wait for the fermentation, or crush the gem, which was mined in the only, unimaginably distant mine in the territory of modern Afghanistan. Ultramarine (lapis lazuli) was valued more than gold and passed through many hands before reaching the artist.
The production of dull blue wig indigo was terribly fetid. In the Middle Ages, indigo began to be delivered from India, where a wyda was discovered with much stronger coloring properties than Central European, and the Indian indigo gradually drove it out of the market.
The green pigment chlorophyll contained in the leaves is responsible for the production of oxygen, without which life on Earth would not be possible. Unsurprisingly, in many cultures, green is considered sacred. This is especially true for regions where the landscape is almost devoid of greenery, such as deserts.
For centuries, green has meant mortal danger. Often this color depicted poison. In earlier times, the composition of green pigments included toxic metal oxides (for example, copper oxide), impregnated with no less toxic arsenic. If the artist decided to lick the brush, he would have lost his life! So, according to one legend, Napoleon fell victim to interior design: his room was papered with green wallpaper that had arsenic in the dye.