The “Cave of Skulls” during excavations, in 2015-2016 (Photo: Yoli Schwartz, Israel Antiquities Authority).
The earliest archaeological evidence of red-dye fabric using scale insects has been uncovered in the caves of the Judean Desert, according to a new joint study by the Israel Antiquities Authority (IAA), Bar-Ilan University, and Hebrew University of Jerusalem.
Researchers identified the rare 3,800-year-old textile’s color as being derived from oak aphid insects, known in the Bible as “Tola‛at Hashani” (literally the “scarlet worm”).
In 2016, the rare textile, less than 2 cm in size, was discovered in the “Cave of Skulls” during excavations led by Dr. Eitan Klein, Dr. Uri Davidovich, Roi Porat and Amir Ganor of the IAA and the Hebrew University. The excavation aimed to protect heritage artifacts in the Judean Desert caves from antiquities looting.
The minuscule red textile, along with dozens of others, was promptly sent for more analysis. Using carbon-14 dating, the textile was determined to be from the Middle Bronze Age (1767-1954 B.C.).
The piece of textile with a bright red hue highly contributed to a comprehensive research project to identify dyes in archaeological textiles, led by Dr. Naama Sukenik from the Israel Antiquities Authority, Prof. Zohar Amar, and Prof. David Iluz from Bar-Ilan University, published in the ‘Journal of Archaeological Science.’
The red hue comes from a dye called “kermes,” which is produced by a genus of scale insects in the order Hemiptera. They feed on the sap of oak trees and the females produce the red dye known as kermes.
According to scholars,the red textile from the “Cave of Skulls” is considered unique as it represents the earliest known example of woolen cloth dyed with kermes. Despite the extensive historical records detailing the widespread use of scale insect dyes in the ancient world, very few fabrics dyed with kermes from before the Roman period have been found. This makes the textile a significant and rare find.
Davidovich highlighted the importance of the find, saying the discovery links historical records with archaeological evidence and demonstrates how ancient people had the expertise to dye wool fibers red using scale insects as early as the Middle Bronze Age.
Sukenik added that the rare textile points to extensive international trade networks and implies the existence of an elite society during that early period.
In the Bible, the color scarlet is mentioned 25 times, frequently in conjunction with purple (Argaman) and blue (Tekhelet), which were regarded as the most valuable and prestigious colors in the ancient world. It appears in references to luxurious clothing, textiles for the priest’s clothes, for the Tabernacle and temple, and various ceremonial uses.
“In ancient times, the red dye was derived from the female scale insect residing on the kermes oak tree (Quercus coccifera),” explained Sukenik, who is also the curator responsible for the Organic Material Collection at the IAA.
The insects were harvested during a single month in the summer when the dye concentration was at its peak. The challenge of locating the small camouflaged insects, the brief harvesting window, and the limited dye yield rendered the scarlet hue exceedingly expensive and reserved for wealthy people.
Prof. Amar pointed out that in the Bible, the dye extracted from oak scale insects is referred to as “scarlet worm.” Historically, the term “worm” encompassed various insects and their developmental stages.
The biblical connection of this color to a living organism demonstrates remarkable zoological insight, especially considering that female scale insects are legless and wingless, leading some Greco-Roman naturalists during antiquity to mistake them for plant matter.
References to the red dye derived from kermes can be also found in ancient trade documents, such as some cuneiform tablets from Mesopotamia dating back to 1425 B.C.
A fragment of a rare 3,800-year-old textile, dyed with the Kermes vermilio insect. (Dafna Gazit, Israel Antiquities Authority)
Throughout history, various species of scale insects have been used to produce red dye. Until today, in South America, another species of cochineal scale insect living on certain plants is used for dyeing textiles.
A sophisticated analytical technique determined the dye’s origin down to the specific species of scale insect. Dr. Sukenik explained that the dye in the ancient fabric was identified through High-Performance Liquid Chromatography (HPLC), an instrument frequently employed in biological and chemical laboratories to separate and analyze substances in small amounts. Consequently, it is very likely that the textile was colored using a species of Kermes vermilio, which produces kermesic acid, giving the fabric its characteristic red shade.
Professor Iluz, who heads the Environmental Sciences and Agriculture Department at Beit Berl College, highlighted that the species identified in this case is Kermes vermilio, which lives on a species of oak trees that is found in the central and eastern Mediterranean regions, including Spain, France, and other areas – but not in Israel.
While Israel does have a native scale insect species on Palestinian oak (Quercus calliprinos) capable of producing a red-orange tint, the analytical results confirm that the dye in this instance is from the non-native Kermes vermilio, demonstrating that international Mediterranean trade was already well-established during that time.
Other dyeing methods, including those using sea snails, were also costly. The Tyrian purple, or royal purple, for instance, was a renowned dye during antiquity. As far back as the 15th century B.C., the inhabitants of Sidon and Tyre, two coastal cities in ancient Phoenicia, were already extracting purple dye from the spiny dye-murex, a type of sea snail.
It was used and industrialized, for instance, by the Israelites at Tel Shikmona near modern Haifa, but the Phoenicians had quite a monopoly on this industry.