Discovery of Dibromoindigo – German chemist Paul Friedlander identified the chemical structure of the purple dye from the Murex snail as being 6,6’-dibromoindigo.
1913 Rabbinical Investigation – R. Isaac Herzog’s doctoral thesis on Techeles named the Murex trunculus as the “most likely candidate” for the source of Techeles – except that, by using contemporary dyeing procedures, its dye was not pure blue.
1980 Discovery of Process to Obtain Blue Dye – Prof. Otto Elsner of the Shenkar College of Fibers in Israel discovered the secret of producing a pure blue color from the Murex trunculus snail, thus solving Herzog’s most compelling difficulty. Together with Ehud Spanier of Haifa University, he investigated the photo-chemical properties of the trunculus dye and found that when the dye is in a reduced state (a prerequisite for dyeing wool), exposure to ultra-violet light will transform the blue-purple colorant (dibromoindigo) to unadulterated blue (indigo).
1985 Rabbi Eliyahu Tavger – While writing his book (K’lil Techeles) about tzitizis, R. Tavger became convinced that the source of authentic Techeles had been in fact discovered. Determined to actualize his newfound knowledge, and after much trial and error, he succeeded in applying the process according to the halakha from beginning to end – thus becoming the first person since its loss to dye Techeles for the ritual purpose of tzitizis.
P’til Techeles – Together with R. Tavger, the P’til Techeles organization was formed to produce and distribute Techeles strings, as well as to promote research and educational projects.
