The Phoenicians were the first people to color clothes with a purple dye derived from the Murex sea snail, and this Tyrian Purple became synonymous with royalty and enormous wealth.
The Phoenicians pioneered a costly purple dye from Murex snails, which became known as Tyrian or Imperial Purple and was worn by emperors of Assyria, Rome, and Byzantium.
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Paul Cooper: The Phoenicians of Tyre and other cities were the first people to color their clothes with a particular kind of dye derived from the bodies of predatory sea snails known as the Murex, or rock snail. These snails produce their dye as a defense mechanism against predators... It could take more than 50 kilograms of these snails to make a single gram of dye, and so, these fabrics were extremely expensive. The color purple would soon become associated with enormous wealth, and as a consequence, with royalty.