True Blue

“Speak to the Children of Israel and bid them  make fringes on the corners of their garments throughout their generations, and put upon the fringe of each corner a thread of blue.” [i]

Pious Jews, to this day, wrap themselves  in special religious garments, called tallitim (singular: tallit),  for daily prayer. Yet for  fifty-odd generations, their intricately knotted fringes have been pure white, without a trace of  blue.  This is because the Biblical purple-blue dyeing methods, had become lost over time.    

From generation to generation,  however, scholars studying the Talmud, a compendium of Jewish knowledge   compiled while   these dye-methods  were still  in use, have  discovered   that  these blue  threads were  produced by  the “blood” of a  snail.  

The Talmud [ii] also cryptically notes that  this creature is “similar to  the sea,  similar to a fish, yields  a steadfast shade similar to the sea,” and using a   Talmudic metaphor denoting  rarity and worth, “ appears once every 70 years.”  Pliny the Elder, who lived at the height of purple-blue popularity, notes,  in his Natural History, that though the snail’s “blood” emits an offensive odor, “on every garment it sheds a luster. ” 

Archeologists  have traced  the  origins of this dyeing industry  to  ancient Crete and Egypt. It  evidently reached Phoenicia. which became the  purple-blue dye center  of the  world.

In ancient times, people  usually  wore dull-colored  raw wool garments. So adorning  them with even a single strand of  blue, the product of a staggering number  of snails, commanded  attention.  Anyone donning garments  completely swathed  in purple-blue, like the High Priest of Jerusalem, commanded  great respect as well.   No wonder the Romans, who ruled this part of the world from 63 BC through 330 AD, reserved these costly dyes for robes of royalty, for leaders  “born to the purple.”   The Mediterranean dyeing industry eventually went underground. By  the Arab Conquest of Israel in  638 AD, it had disappeared entirely.    

In recent  years, however, the lost secrets of   purple-blue dye production have  come to light.  Marine biologists, combining  ancient knowledge  with modern  techniques, discovered that the Murex trunculus  sea-snail alone contains a   gland which produces these dye-enzymes.  Archeologists, consistent with these  findings,  have  discovered great mounds of broken  murex shells, ringed with purple-blue dyes.  strewn around Mediterranean Roman Period  dye-pits,  

Although the chemistry of these dyes  do match those produced by modern-day  murex, two  key Talmudic  descriptions still defied description.  Modern murex dye yields  a shade decidedly  more purple than sea-blue– and is hardly    “similar  to the sea.”  

“Similar to the sea” soon  became clear.   Murex is    rough,   whorled, and  brownish-white  when held in hand.  In its  natural state,  however, coated with sea-slime, it is  nearly indistinguishable from  its home, the seabed .  

The second purple-or-blue puzzle was solved  by chance.  When Prof. Otto Elsner of Tel Aviv’s Shenkar College of Fibers inadvertently left an  enzyme-infused cloth in  direct sunlight, to his delight, it turned bright blue.  Murex  dye, he discovered, is  light-sensitive. 

Today  Ptil Tekhelet, a modest workshop outside Jerusalem, recreates the  ancient purple-blue dyeing craft anew.  There,  pious Jews, like their forefathers, hand-spin soft merino wool into thread, then twist it into tight multi-ply strands. As of old, they also  consecrate each step with the traditional prayer, “ thus  I fulfill the commandment of the fringes. ”    

The  original  murex-dye method required  ground  limestone and a variety of acids used over a period of ten days.  Using modern chemicals and techniques, Ptil Tekhelet    produces identical results within hours.    

Their woolen threads,  when  first  removed from  the yellowish dye,  are yellowish.  On  exposure to air, however, they   immediately change color.  These rainbow strands  deepen as they dry, ranging  from purple to palest blue.

After  they are incorporated  into  fringes, bits of  blue    among the white, they are hand-knotted and attached to prayer shawl corners according to a variety of  complex religious and  numerological traditions. As it is written,  in the Beginning, God  divided  the waters from the waters, forming the sea, forming the sky.  The sky changes with the passing hours, and the sea–now purple, now blue– reflects the changing skies. And the blue tallit fringes  resemble the sea,  which resembles the sky, which resembles Infinity of the Creator.  


[i] Numbers 15:38-39 

[ii] Babylonian Talmud, Menahot 44a