Rediscovery
Over the last two centuries, attempts have been made to identify the ancient source of the dye by comparing Talmudic sources to physical evidence. Three types of mollusks have been proposed as the lost khillazon. None have been universally accepted, though the Murex, Murex trunculus, known by the modern name Hexaplex trunculus is thought to be the most likely source of the biblical blue dye. Most Rabbinical Jews continue to wear only white tzitziyot, following their poskim (deciders of Jewish law).
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