A (very) brief introduction to Murex Techeiles

The Mitzva of Tzitzis has two components, one being lavan (white strings) and the other, techeiles (blue strings dyed with the blood of the chilazon). The identity of the chilazon and/or the dyeing process needed for techeiles was lost between the conclusion of the Amoraic period and the beginning of the Geonic period. Many theories, including the Arab conquest of 639 CE and a decree of the Roman Empire against its use, are given to explain the cause of its loss.

Now let us explore some of the main identifications of the chilazon. Rashi (Avodah Zarah 28b) translates chilazon as limace, which is old french for snail. The Pesikta D'Rav Kahana (11:21) says that the chilazon is a creature with a growing shell. Furthermore, the Gemara in Menachos (43a) implies, as the Rambam (Tzitzis 2:1) clearly writes, that its dye is extremely fast. The Gemara in Shabbos 75a implies (according to Tosafos there) that the chilazon has two "bloods", its lifeblood and a secretion used for its dye. Lastly, the Gemara in Shabbos 26a says that the chilazon was trapped on the Mediterranean shores from Haifa to Tzor (Tyre in ancient Phoenicia). Hence, we are looking for a snail with a fast, blue dye with two separate bloods, which was mainly concentrated around the site of ancient Phoenicia.

The Shiltei Hagiborim (by R' Avrohom Harophe, a prominent 16th-17th century Italian Torah scholar), the Chavos Yair, and other Acharonim clearly state that the chilazon used for techeiles is a species called Purpura. There are also indications in Midrashim which associate royal techeiles clothing with a cloak called purphira. Furthermore, the Talmud Yerushalmi, quoted by the Ra’avya clearly identifies a techeiles dyed garment with purphira.

A new possible candidate for the chilazon has been discovered; a snail called the Murex Trunculus. Based on many ancient Greek writings, this snail can clearly be identified as the Purpura; and in fact, to this day, the Murex which is consumed in Greece, is called purpura there.

The Murex Trunculus fits all the above descriptions. It is a snail with a very fast dye and in fact, is praised by ancient scholars for its fastness. The Murex also contains two bloods which corresponds to the Gemara in Shabbos 75a. It is documented that the ancient center for murex dyeing was in Phoenicia, and Phoenicia's most famous industry was the tyrian colors of purpura. Incidentally, techeiles is called "tyrian" by the Midrash in Vayishlach (see Aruch טריון). Rav Yaakov Emden clearly writes that popular dye of Tyre is the same thing as the techeiles of Chazal. Recent excavations of ancient Phoenician sites disclosed enormous amounts of Murex shells which were broken open in the manner needed to extract its dye.

One problem still remained. After the extraction of the dye sac from the Murex, a black mucus was obtained, which after exposure to oxygen changed to purple, unlike techeiles which is assumed to be blue. However, in the early 1980's, it was discovered that if exposed to direct sunlight during the dyeing process, the Murex's dye will change from purple to blue.

(In more recent years, after more experimentation, more ways to produce a blue dye were discovered, which can be done indoors as well.)

The Gemara in Shabbos 75a tells us that it is preferable to extract the chilazon's dye as soon as possible after its death. This is consistent with the process of extracting the dye from the Murex, as it was proven by recent experimentation that the dye lost some of its quality when extracted a half hour after the death of the snail.

The Gemara in Menachos 44b states that "the appearance of the body of this chilazon is like the sea, and its form is like that of a fish". Until it is professionally polished (even after being thoroughly brushed), presumably due to its rough shell, algae will remain on it, giving it a sea-like color; and the shape of the Murex shell is strikingly similar to the shape of a standard fish (the head, body, tail etc.).

In conclusion, we quote the Teshuvos Maharil (Chadashos 5:2) who writes that the use of techeiles can return at any time, and that one can identify the chilazon using simonim (a tradition regarding its identity is not needed). It follows that if found, it should definitely be used for tzitzis.

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