朱砂 and Other Red Dyes

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(1) vermilion  朱砂
https://en.wikipedia.org/wiki/Vermilion
(section 2 Etymology: 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)
(a) chemically: HgS 硫化汞 (toxic)
(b) Latin English dictionary
vermis (noun masculine): "worm"
https://en.wiktionary.org/wiki/vermis
(c) 朱砂, from mineral, has been used in China as both a dye and in Chinese medicine.

(2) kermes (dye)
https://en.wikipedia.org/wiki/Kermes_(dye)
(Kermes is a red dye derived from the dried bodies of the females of a scale insect in the genus Kermes, primarily Kermes vermilio; Following the Spanish conquest of the Aztec Empire, Mexican cochineal, which produced a stronger dye and could thus be used in smaller quantities, replaced kermes dyes in general use in Europe)
(a) Both English words crimson and kermes came from the same Medieval Latin cremesinus -- crimson through Old Spanish cremesin "of or belonging to the kermes" (according to the same dictionary identified next, on “crimson”) whereas kermes through French -- in turn from Arabic qirmiz "kermes," from Sanskrit krmi-ja.

* kermes (n). Online Etymology Dictionary, undated
www.etymonline.com/index.php?term=kermes
(b) The old nomenclature of Kermes vermilio is Coccus ilicus.

(3) Chemically, kermes (dye) is made up of kermesic acid, whose sole difference with carminic acid is the former does not have the glucose molecule.  See Allevi P et al, A Simple Transformation of Carminic Acid into Kermesic Acid. Journal of Organic Chemistry, 52: 5469-5472 (1987)
pubs.acs.org/doi/pdf/10.1021/jo00233a033
(at 6459: "Carminic acid ([Fig] 1a) is the principal component of food dye cochineal, obtained from the insect Dactylopius coccus * * * The aglycon moiety of carminic acid is represented by kermesic acid (1b), the coloring matter of kermes, the most ancient dyestuff on record")

The 3-D conformation of Glucose -- never flat -- assumes either boat- or chair-shape (the latter has “the lowest total energy, and are therefore the most stable”). The two forms shifts back and forth for the same molecule of glucose.  A boat form is when both flaps point to the same (ie, not opposite) direction.

(4) In ancient China red dye is extracted from root of madder. See Rubia cordifolia
https://en.wikipedia.org/wiki/Rubia_cordifolia

, whose red dye molecules are all anthraquinones. Please recall a molecule of carminic acid is composed of 1 anthraquinone and 1 glucose.