Venetian red
Venetian red is a light and warm (somewhat unsaturated) pigment that is a darker shade of red. The composition of Venetian red changed over time. Originally it consisted of natural ferric oxide (Fe2O3, partially hydrated) obtained from the red hematite. Modern versions are frequently made with synthetic red iron oxide produced via calcination of green vitriol (a.k.a. copperas) mixed with white chalk. The pigment contains up to 50% of the ferric oxide.
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