Blue of Heaven and Golden Glitter of Sun

The blue stone 'lapis lazuli' was for the ancient Egyptians the real thing. Its colour combines the blue of the heaven and the golden glitter of the sun. In the ancient Egyptian language  it's called 'ḫsbḏ'. The colour of the cosmos, fertility, sustance and rebirth. But this stone was rare and expensive because it had to be imported, via Mesopotamia, from the Kokcha River valley in Afghanistan (Sar-i Sang mines).

Scarab made from lapis lazuli: 

To meet the high demand of blue the ancient Egyptians invented the pigment called Egyptian blue. The term for it in the ancient Egyptian language is 'ḫsbḏ-ỉrjt', which means 'artificial lapis lazuli'. Unknown is who invented it, where and how. By accident just like glass-making? In our time and age Egyptian blue is known as calcium copper silicate. A mixture of silica, lime, copper, and an alkali. It was first synthesized during the Fourth Dynasty (ca. 2613 BC–ca. 2494 BC) and used extensively until the end of the Roman period in Europe (400 AD). No written information exists in ancient Egyptian texts about the manufacture of Egyptian blue. It was first mentioned only in Roman literature by Vitruvius during the first century BC.

 

Egyptian blue on a fragment showing Nebamun hunting in the marshes around 1350 BC.

Recipe to make this pigment (source: NILE, september 2021):

Recipe according to Vitruvius, 'De Architectura', Book VII, Chapter 11 (here):

In the early Christian tradition lapis lazuli was regarded as the stone of the mother of Jezus, Mary. The blue of the heaven and the golden glitter of the sun. The stone of Mary.

P.S. The scarab is on display in The Met as 26.7.755: here.  The hunting scene is on display in the Michael Cohen Gallery of the British Museum: here.