Purple called natural dye, which is derived from the shells of mollusks murex brandaris - red algae or iglyanok. Discoverers believe purpura Phoenicians. Even the name "Phoenicia" comes from the Greek "foynikes" - "purple" or "country purpura."
To get the purple, mollusk shells are ground and dried in the sun, so that the powder has acquired the desired color. Shades of purple - from crimson to purple. In ancient times, this dye due to the complexity of its production was incredibly expensive, it is literally worth its weight in gold. Most often used to paint purple fabrics, clothing of which were only noble class. That is why the color purple became a symbol of wealth and power. Now almost purple is not used due to the high prices of production and replaced by synthetic dyes.