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How we see color
There are three types of color receptors in your eye: red, green and blue. But how do we see the amazing kaleidoscope of other colors that make up our world? Colm Kelleher explains how humans can see everything from auburn to aquamarine.

History’s deadliest colors
When radium was first discovered, its luminous green color inspired people to add it into beauty products and jewelry. It wasn’t until much later that we realized that radium’s harmful effects outweighed its visual benefits. Unfortunately, radium isn’t the only pigment that historically seemed harmless or useful but turned out to be deadly. J. V. Maranto details history’s deadliest colors.


Additional references

Why is purple considered the color of royalty? - History
The color purple’s ties to kings and queens date back to ancient world, where it was prized for its bold hues and often reserved for the upper crust. The reason for purple’s regal reputation comes down to a simple case of supply and demand.

Tyrian purple - Ancient History Encyclopedia
Tyrian purple (aka Royal purple or Imperial purple) is a dye extracted from the murex shellfish which was first produced by the Phoenician city of Tyre in the Bronze Age. Its difficulty of manufacture, striking purple to red colour range, and resistance to fading made clothing dyed using Tyrian purple highly desirable and expensive.

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