Tyrian Purple (also called Royal Purple) dyes clothes a deep purple shade. In ancient times, it was extracted from the Mediterranean sea snail (Murex brandaris).
The extraction and trade of Tyrian Purple has been recorded since the 4th c. BC. Pliny the Elder, the famous Roman historian and scientist, has left us a description of how it was made:
After the snails are fished from the sea, the dye-bearing vein is extracted and crushed. For every hundred pounds of the juice, 20 ounces of salt are added, and left for three days. It is then set to boil slowly in vessels of tin [or lead], to concentrate the dye, for up to ten days. Then the cloth to be dyed is immersed into the boiling mixture. The boiling is continued until the cloth is dyed to the satisfactory shade. Red shades are considered inferior to blackish ones. Finally the cloth is left to soak until it has fully imbibed the colour. [x]
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