The Lydians and their neighbors were famed for their skill in the dyeing of purple since the days of Homer, in the ninth or eighth century B.C.E. Indeed, Thyatira’s water was reputed to produce “the brightest and the most permanent hues.”
Purple materials were luxury items, accessible only to the rich. Although different sources for purple dye were known, the best and most expensive—used for treating fine linen—came from Mediterranean shellfish. A single drop of dye could be extracted from each mollusk, and some 8,000 shellfish had to be processed to obtain just one gram of the precious liquid; thus, cloth of that color was very costly.