Professor Hoffman extracts the hypobranchial gland from the Murex Trunculus snail. This was the source of then ancient blue dye known as tekhelet.
La couleur pourpre du Murex / Murex extracted purple color
Murex Snail & Ancient Dye Technique (First Century Foundations 5/6)
Tyrian Purple | History of Colors | LittleArtTalks
Purple Dye From Phoenicians
Purpura Dyers - Oaxaca
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