The vein already mentioned is then extracted and about a sextarius of salt added to each hundred pounds of material. The process is described by Pliny, writing in the 1st century AD: But it is clear that the dye does not exist in the mollusc and is generated from precursors, sometimes termed chromogens, contained in the hypobranchial gland. Surviving details of the ancient process are insufficient to explain the chemistry involved and this is the subject of continuing speculation. The ancient industry was distributed world-wide. This molluscan dye has been known since pre-Roman times and in the Mediterranean region there is evidence for the industry around the 13th century B.C. This review attempts to set the record straight. The long history, stretching back well into the pre-chemical era, and embracing chemistry, biology and sociology, contains not a few misconceptions and erroneous conclusions. The colour is derived exclusively from marine shellfish of the Muricidae and Thaisidae families.
Arguably, it is the oldest known pigment, the longest lasting, the subject of the first chemical industry, the most expensive and the best known. 6,6’-Dibromoindigo is a major component of the historic pigment Tyrian purple, also known as Royal purple, shellfish purple and Purple of the Ancients.
0 kommentar(er)
