Tekhelet ( ) is a blue dye that historically held great significance in ancient Mediterranean civilizations. It is mentioned in the Hebrew Bible and is accordingly commonplace in Jewish culture, wherein it features prominently to color the fringes (called tzitzit) of several Jewish religious garments, such as the tallit. The dye was similarly used in the clothing of the High Priest of Israel and in tapestries in the Tabernacle.
Biblical texts do not specify the source or production method of tekhelet. Rabbinic literature, however, records that it was produced from a marine animal: (). The practical knowledge of tekhelet production was lost over time, resulting in the omission of the dye from tzitzit. The ḥillāzon has been identified in contemporary times as Hexaplex trunculus.
Biblical references Of the 49 or 48 uses of the word tekhelet in the Masoretic Text, only one refers to fringes on cornered garments of the whole people of Israel (). Six are non-ritual uses, such as Mordechai dressing himself in tekhelet before the King of Persia (Esther 8:15). Tekhelet could be used in combination with other colors as in 2 Chronicles where the veil of Solomon's Temple is made of tekhelet, Tyrian purple () and scarlet ( or ). mentions that tekhelet-cloth could be obtained from "isles of Elishah" (Cyprus). All Biblical mentions of tekhelet imply that it was difficult to obtain and expensive, an impression corroborated by later rabbinic writings.
History
The manufacture of tekhelet is believed to date back to at least 1750 BCE. In the Amarna letters, dated to the 14th century BCE in the New Kingdom of Egypt, tekhelet garments are listed as a precious item in a royal dowry.
Data about the dye seems to have been lost sometime after the period of the savora scholar Ahai (5th–6th century). The 8th century Tanhuma is the first written source to lament this loss.
In his doctoral thesis (London, 1913) on the subject, Yitzhak HaLevi Herzog proposes H. trunculus (then known as Murex trunculus) as the most likely candidate for the source of the dye.Hebrew Porphyrology Though H. trunculus fulfilled many of the Talmudic criteria, Herzog's inability to consistently obtain blue dye from the snail precluded him from declaring it to be the dye source.
In the 1980s, Otto Elsner, a chemist from the Shenkar College of Fibers, Israel, discovered that if a solution of the dye was exposed to ultraviolet light such as from sunlight, blue instead of purple was consistently produced.O. Elsner, "Solution of the enigmas of dyeing with Tyrian purple and the Biblical tekhelet", Dyes in history and Archaeology 10 (1992) p 14f. Elsner's discovery of that exposure to sunlight turns the red 6,6'-Dibromoindigo extracted from the hypobranchial gland of H. trunculus snails into a mixture of blue indigo dye and blue-purple 6-bromoindigo was widely viewed as resolving Herzog's issue.
In 1988, Rabbi Eliyahu Tavger dyed tekhelet from H. trunculus for the commandment of tzitzit for the first time in recent history. Based on this work, four years later, the was founded to educate about the dye production process and to make the dye available for all who desire to use it.
Color
The exact hue of tekhelet in antiquity is not definitive. The color of tekhelet was likely to have varied in practice, as ancient dyers would have lacked the capability of producing precise shades from one batch of dye to another.Robert Laird Harris, Gleason L. Archer and Bruce K. Waltke, Theological Wordbook of the Old Testament, (Chicago, 1980/2013) [TWOT] (CD-ROM), 2510.0. Modern scholars believe that tekhelet probably referred to blue to blue-purple colors.Shiyanthi Thavapalan, "Purple Fabrics and Garments in Akkadian Documents", Journal of Ancient Near Eastern History, 2018,
In the early classical sources (Septuagint, Aquila, Symmachus, Vulgate, Philo, and Josephus), tekhelet was translated into Koine Greek as hyakinthos (, "alpine squill") or its Latin equivalent.Efraim Vaynman, Tekhelet: Color Perception or Apprehension? The flower of the alpine squill ranges from a violet blue to a bluish purple, and the word hyakinthos was used to describe both blue and purple colors.
Early rabbinic sources provide indications as to the nature of the color. Some sources describe tekhelet as visually indistinguishable from indigo ( ). This description is also somewhat ambiguous, as different varieties of indigo have colors ranging between blue and purple, but generally the color of dyed indigo in the ancient world was blue.Baruch Sterman, Tekhelet Perception
Other rabbinic sources describe tekhelet as similar to the sea or sky. An oft-repeated explanation for the Torah's choice of tekhelet went as follows: "Why is tekhelet different from all other colors? Because tekhelet is similar [in appearance] to the sea, and the sea is similar to the sky, and the sky is similar to lapis lazuli, and lapis lazuli is similar to the Throne of Glory."Chullin 89a; similarly Menachot 43b, Sotah 17a, Sifre to Numbers 15:38; Numbers Rabbah 17:5 (In a few versions of this source, "plants" are included in this chain of similarity even though plants are not blue;Numbers Rabbah 14:3; Jerusalem Talmud Brachot 1:2 though it has been suggested that these sources refer to bluish plants like hyacinth.)
In other sources, the color of the tekhelet is compared to the night sky.Shabbat 99a; in Sifrei Bemidbar 115 the color is compared to both the sea and the night sky (ר' אלעזר בר"ש אומר, למה נקרא שמה תכלת ע"ש שנתכלו המצרים בבכורות. שנאמר ויהי בחצי הלילה וה' הכה כל בכור. ד"א על שם שכלו המצרים בים.) Rashi quotes Moshe ha-Darshan who describes it as "the color of the sky as it darkens toward evening" – a deep sky blue or dark violet.
Rashi himself describes the color as "green" () and "green, and close to the color of leeks",Rashi to Brachot 9b: ירוק הוא וקרוב לצבע כרתי שקורין פור"ייש; the last word transliterates the French poireau the latter commenting on a Talmudic passage according to which the morning Shema may be recited once it is light enough to distinguish between tekhelet and leeks. However, other rabbinic texts comment that "the appearance which is called in the language of Ashkenaz bleu () is within the category of green"Shulchan Aruch, Yoreh Deah 188:1; see also blue–green distinction in language suggesting that Rashi's language does not necessarily rule out a blue color.
The Sifrei says that counterfeit tekhelet was made from both "[red] dye and indigo", indicating that the overall color was purple. However, other sources list just "indigo" as the counterfeit, suggesting either that in their opinion the color was purely blue, or that indigo was the main counterfeit ingredient and the other ingredients not significant enough to mention.
The Sippar Dye Text (7th century), as well as the Leyden papyrus X and Papyrus Graecus Holmiensis (3rd century) provide recipes for counterfeit takiltu that includes a mixture of red and blue colors, for an overall purple color.
A pure blue can only be produced from Hexaplex dye through a debromination process. The creation of blue Hexaplex dye using this process was only discovered in the 1980's, leading some experts to conclude that ancient dyers would not have been able to create blue tekhelet (and, therefore, that an undebrominated purple color is more likely). However, in recent years archaeologists have recovered several fabrics dyed blue with Hexaplex dye 1800 or more years ago, demonstrating that ancient dyers could and did make blue dye from Hexaplex. Such fabrics have been found at Wadi Murabba'at (2nd century), Masada (1st century BCE), Qatna (14th century BCE),James, Matthew et al, "High prestige Royal Purple dyed textiles from the Bronze Age royal tomb at Qatna, Syria", Antiquity 83:1109–1118 (2009) and arguablyEfraim Vaynman, A Testament to the True Tekhelet the Pazyryk burials (5th–4th century BCE).
Source – Identifying the ḥillazon While the Bible does not identify the source of tekhelet, rabbinic texts specified that it could only be made from a sea creature known as the ḥillāzon. Various animals have been suggested as the ḥillazon.The International Standard Bible Encyclopedia – Page 1057 Geoffrey W. Bromiley – 2007 "The most highly prized dye in the ancient world obtained from the secretions of four molluscs native to the eastern Mediterranean: Helix ianthina, Murex brandaris, Murex trunculus, and Purpura lapillus. Various shades could be produced"
Rabbinic sources describe several qualities of this animal. It was found on the coast between Tyre and Haifa.Shabbat 26a "Its body is similar to the sea, and its form (ברייתו) is similar to a fish, and it comes up [from the sea] once every 70 years, and with its blood tekhelet is dyed, therefore it is expensive." Dye was extracted from the Ḥillazon by cracking it open, suggesting that it has a hard external shell. Another source suggested that just as the Hebrews' clothing did not wear out in the desert (), the shell of the ḥillāzon does not wear out.Devarim Rabbah 7:11
Garments dyed with tekhelet and indigo have such a similar appearance that it was said only God can distinguish them.Bava Metzia 61b One opinion states that there is no chemical test which can distinguish between tekhelet and indigo wool, but another opinion describes such a test and tells the story of it working successfully.Menachot 42b Trapping the ḥillāzon is considered a violation of Shabbat. In the time of the Talmud, the ḥillāzon was used as part of a remedy for hemorrhoids,Avodah Zarah 28b though this may refer to a different species of snail.
Hexaplex trunculus
Arguments for Hexaplex trunculus
The dye produced by Hexaplex has the exact same chemical composition as indigo, corresponding to the statement that only God can distinguish the tekhelet from indigo garments.
In the area between Tyre and Haifa where the ḥillāzon was found, piles of murex shells hundreds of yards long have been found, apparently the result of dyeing operations. In Tell es-Samak on the coast near Haifa, a "biblical era purple dye workshop" of the Phoenicians was found, including relics of purple dye produced from sea snails, as well as textile-manufacturing equipment.
Chemical testing of ancient blue-dyed cloth from the appropriate time period in Israel reveals that a sea snail-based dye was used. Since murex dye was available, very long-lasting, and visibly indistinguishable from indigo-based dyes, but also not specifically prohibited as counterfeit despite being known, it is argued that H. trunculus (or one of the other two indigo-producing sea snails) must have been the ḥillāzon or at least deemed as acceptable to use interchangeably.
The word ḥillāzon is cognate to the Arabic word (), meaning snail. Hexaplex opponents suggest that in ancient times the word might have referred to a broader category of animals, perhaps including other candidate species such as the cuttlefish.
Another Talmudic requirement is that the dye cannot fade, and the H. trunculus dye does not fade and can only be removed from wool with bleach.
The Talmud states that the ḥillāzon is preferably kept alive while the dye is extracted, as killing it causes the dye to degrade. This matches both ancient descriptions of the Hexaplex dyeing process and also modern experience that an enzyme in the snail needed for dye production decays quickly after death.
The Jerusalem Talmud as quoted by Raavyah translates tekhelet as porporin; similarly Musaf Aruch translates tekhelet as parpar. These translations refer to the Latin term purpura, meaning the dye produced by Hexaplex snails. Similarly, Yair Bacharach stated that tekhelet was derived from purpura snails, even though this forced him to conclude that the colour of tekhelet was purple (purpur) rather than blue, as in his era it was unknown how to produce blue dye from Hexaplex.