03-21-2014, 08:49 AM
So far as I can tell, there was no 'green' dye as such. The assumption is that a green colour can be achieved by 'over dying', I.e. Dyeing first with yellow and then with blue. Two dye baths would make this an expensive way to dye a garment, though.
Just to take up a point made further back, cochineal is a dye that would not have been known to the Romans. It is derived from the dried bodies of an insect that feeds off cacti that grow in Mexico. However, a near substitute would have been kermes. This is obtained from insect eggs and, like cochineal, yields a scarlet dye. I think the two are chemically related, possibly hydroxylated anthroquinone carboxylic acids (just showing off here, hope I am correct now!)
Mike Thomas (Caratacus)
Just to take up a point made further back, cochineal is a dye that would not have been known to the Romans. It is derived from the dried bodies of an insect that feeds off cacti that grow in Mexico. However, a near substitute would have been kermes. This is obtained from insect eggs and, like cochineal, yields a scarlet dye. I think the two are chemically related, possibly hydroxylated anthroquinone carboxylic acids (just showing off here, hope I am correct now!)
Mike Thomas (Caratacus)
visne scire quod credam? credo orbes volantes exstare.