Murexian dye is a compound derived from murex that can be used to add a vibrant iridescent purple coloration to textiles, metals, and other materials. The difficulty in obtaining and converting murex makes murex-dyed materials highly valuable, and the supply chain of the dyes themselves is under tight control of the Esterfell Accord.
A vial of pure murex can be processed with alchemist's supplies into 5 vials of dye with a successful DC 20 Intelligence check. On a failure, the compound explodes from the vial and deals 2d4 Poison damage to the user.