Vermilion is a deep, brilliant shade of which colour?

Vermilion (sometimes spelled vermillion) is both a brilliant red or scarlet pigment, originally made from the powdered mineral cinnabar, and the corresponding color.

The word vermilion came from the Old French word "vermeillon", which was derived from "vermeil", from the Latin "vermiculus", the diminutive of the Latin word "vermis", or worm. The name originated because it had a similar color to the natural red dye made from an insect, the "Kermes vermilio", which was widely used in Europe. The first recorded use of vermilion as a color name in English was in 1289. The term cinnabar was used interchangeably with vermilion until the 17th century when vermilion became the more common name. Now the term "cinnabar" is used in mineralogy and crystallography for the red crystalline form of mercury sulfide.

The technique for making a synthetic vermilion by combining sulfur and mercury was in use in Europe in the 9th century, but the pigment was still expensive. Since it was almost as expensive as gold leaf, it was used only in the most important decoration of illuminated manuscripts, while the less expensive minimum, made with red lead, was used for the red letters and symbols in the text.

Vermilion was also used by painters in the Renaissance as a very vivid and bright red, though it did have the weakness of sometimes turning dark with time.