Reply To: Techeiles 🔵❎🐌☑️🐟

As to the fact that the gemara does not warn against using Murex Trunculus, that can be simply attributed to the fact that the Gemara was only warning against things which people actually would use as a forgery. Kala Ilan would be used as a forgery because it is very cheap. No one would use Murex Trunculus as a forgery seeing that it is just as expensive as the actual Techeiles.

Just for the record, Rav Shlomo Miller holds that the Murex Trunculus is in fact Kala Ilan.