The Blue color has been throughout the history of humanity one of the most quoted, identified by it with royalty and divinity, due to the difficulty of its obtaining.
Blue pigments were used from very old, but more late than others such as red, Black, brown or ochre, easier to get in nature and used already in the art art.

But the most quoted blue pigment came from minerals such as lapis, scarce and rare, and therefore very expensive. The largest lapis deposits are located in the hindukush of Afghanistan, where they are still exploited with procedures very similar to employees more than 3.000 years ago.
The Egyptians cared about those mines large amounts of lapis to obtain the azurite, the dust that provided the blue pigment with which they adorned their artistic works. Its price was so high that even in medieval times still cuadriplicaba the gold.
That’s why towards 3000 BC they sought a way to make their own blue pigment. Little by little they were perfecting the technique, which consisted of grinding silica, lime, copper and an alkaline base, and heat it at 800-900 degrees Celsius. The result obtained is considered the first synthetic pigment in history.
The Egyptians used it to paint wood, papyri and canvases, coloring enamels, inlays and vessels. But especially in the funerary field in masks, statues and paintings of the graves, as they believed that the blue color protected the ᴅᴇᴀᴅ from evil in the other life.
The oldest known example of the pigment dates from about 5000 years ago and was found in the painting of a tomb of the reign of ka-Sen, the last Pharaoh of the first dynasty. In the new kingdom the Egyptian Blue was used abundantly as a pigment being found in statues, paintings of tombs and sarcophagi.
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