Dye is one of 31 Rare Resources in the game and, if present on a map, available from the beginning. It appears as rows of dye plants with red, yellow and blue blossoms and some bowls standing on the ground nearby. Like all rare resources on land, it can be gathered by sending a Merchant from the Market to the resource location. Dye provides the following benefits:main article. Note, that Knowledge is not gathered before the Classical Age but the Greeks may gather Knowledge from the beginning, making an early exploitation of this resource more useful.
Dye is one of five rare resources that reduce research cost, with the other four being Furs, Papyrus, Silk and Silver. The cost reduction is quite significant, so if Dye happens to be available nearby, a merchant should be sent to collect it as soon as possible.
Although the ancient world could use all sorts of materials for dye including lime, ochre (petrified rust), soot, woad and even human urine, the most prized of all dye was derived from the murex, a crustacean whose bodily secretions contained high levels of iodine, producing a beautiful purple colour. So prized and so difficult was it to extract murex dye that only the extremely rich could afford fully purple fabrics. This was the origin of the term porphyrygenitos or "born in the purple", which in Rome meant royalty — lesser men such as senators had to make do with purple coloured trim in their clothing to denote their status.
In Europe the art of dyeing rose to new heights with the direct impact of trade instigated by the Crusades and furthered by the growing cultural awareness of the Renaissance period. The most prized dyes were brazilwood, lac and indigo, which were found only in Asia, although traditional dyes like those from iodine-rich shellfish and woad continued to be used.