once it is light enough to distinguish between tekhelet and leeks. Other Jewish texts comment that "the appearance which is called in the language of Ashkenaz bleu (בלו"א) is within the category of green (ירוק)" suggesting that Rashi's language does not necessarily rule out a blue color. In Akkadian, the cognate word takiltu is written using the word sign also used for lapis lazuli, suggesting they have similar colors. Lapis lazuli can vary between blue and purple-blue, and according to some sources the preferred shade of lapis lazuli in the Near East was purple-blue. However, Mesopotamian mythology asserted that visible sky is a layer of lapis lazuli stone underlying Heaven, suggesting a sky-blue color for the stone. 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 BCE), as well as the Leyden and Stockholm papyri (3rd century) provide recipes for counterfeit takiltu dye that include a mixture of red and blue colors, for an overall purple color. A pure blue color can only be produced from Hexaplex dye through a debromination process. Only in the 1980s did modern scientists learn how to create blue Hexaplex dye using this process, leading some experts to declare 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), and arguably Pazyryk valley (5th-4th century BCE). Identifying the ḥillazon While the Bible does not identify the source of tekhelet, rabbinic halakha specified that it could only be made from a sea creature known as the ḥillazon. Rabbinic sources describe various qualities of this creature. It was found on the coast between Tyre and Haifa. "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