For 1,500 Years, Royal Purple Was Worth More Than Gold. It Came From the Glands of Sea Snails.
For roughly 1,500 years, the dye known as Tyrian purple was the most valuable color in the ancient and medieval world. It was reserved by law for emperors and the highest aristocracy. By weight, it was worth more than gold. And it came from the body of a small predatory sea snail, harvested off the coast of present-day Lebanon by a craft so foul-smelling that the dye-works had to be located outside the city walls.
For roughly 1,500 years, the dye known as Tyrian purple was the most prized and most expensive color in the ancient and medieval Western world. It was named in Roman law and rationed by Byzantine decree. In some periods, wearing it as a private citizen could be a capital offense. By weight, it was worth more than gold.
It came from the body of a sea snail.
Specifically, it came from a small gland of the murex — a predatory marine snail found along the eastern Mediterranean coast. The Phoenicians of the city of Tyre, on the coast of present-day Lebanon, learned how to extract the pigment from the gland. Production began as early as around 1200 BCE. The technique made Phoenician cities wealthy and gave the civilization much of its early international reputation.
The process was slow and notoriously unpleasant. The snails were caught live, often by the thousands, and the small dye-bearing gland was extracted by hand. The resulting pulp was salted and fermented in shallow vats of lead or stone, often in open sunlight, for around ten days. The smell of the fermentation was overwhelming. Ancient writers consistently note that dye-works were located outside city walls and that the workers' clothes and skin retained the odor for life.
The yield was small. By modern reconstruction, roughly 12,000 snails were needed to produce around one gram of usable dye. The hem of a single Roman senator's toga required several hundred thousand. A full imperial purple garment could require millions.
This scarcity was the real reason the color became royal. There simply was not enough of it for anyone but the very top of the social order to wear.
The industry declined as the Byzantine Empire weakened, and what remained collapsed in 1453, when Constantinople fell to the Ottomans and the imperial dye-works closed for good. The detailed knowledge of how to produce true Tyrian purple was lost and was not fully reconstructed until the 20th century.
For 1,500 years before that, the most powerful people in the Western world wore the inside of snails.