Deep, burnt red of the mineral realgar, not orange like its cousin orpiment.
Red Orpiment is a rich red, close to brown.
It can be described as rich, full, medium and fairly saturated.
Set in black, because black reads best on it.
Orpiment, also known as yellow arsenic blende, is a deep-colored, orange-yellow arsenic sulfide mineral with formula As2S3. It is found in volcanic fumaroles, low-temperature hydrothermal veins, and hot springs and may be formed through sublimation.
Read on WikipediaRed is the color at the long wavelength end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–750 nanometers. It is a primary color in the RGB color model and a secondary color in the CMYK color model, and is the complementary color of cyan. Reds range from the brilliant yellow-tinged scarlet and vermillion to bluish-red crimson, and vary in shade from the pale red pink to the dark red burgundy.
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