XPost: alt.art, alt.politics, alt.history
https://scitechdaily.com/5000-year-old-color-reborn-scientists-recreate-ancient-egyptian-blue/
. . .
The recipe had been lost during Roman times.
You can see it on Egyptian tomb walls and
artifacts.
Depending on exact methods, the pigment can be
a light blue-green to a pretty intense blue.
It lasts thousands of years, mostly because it
is mineral-based instead of organic.
Good blue pigment has always been difficult to
obtain. There are a couple of minerals that
are the right color, but they're rare and
historically very expensive. Wasn't until the
18th century that dye-based blues made the
color affordable.
There was one other kind of blue the Egyptians
sometimes used ... they'd basically make cobalt
glass and then grind it to fine powder.
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