https://nammu.com/eng/egyptian-lapis-lazuli/
Historically, blue is a “new” color, and one that was initially reserved only for royalty. It emerged about 6,000 years ago in Afghanistan with the lapis lazuli stone that was hailed by the Egyptians as precious. They used it with gold to create eyes for the pharaoh’s tombs, and even used powdered lapis lazuli to create blue eye shadow for Cleopatra.
now we know why blue
https://ancientegyptonline.co.uk/eye/
The Wadjet (or Ujat, meaning “Whole One”) is a powerful symbol of protection in ancient Egypt also known as the “Eye of Horus” and the “all seeing eye”. The symbol was frequently used in jewellery made of gold, silver, lapis, wood, porcelain, and carnelian, to ensure the safety and health of the bearer and provide wisdom and prosperity.
kek