Kermes is a red dye derived from the dried bodies of the females of a scale insect in the genus Kermes, primarily Kermes vermilio. The Kermes insects are native in the Mediterranean region and are parasites living on the sap of the host plant, the Kermes oak (Quercus coccifera) and the Palestine oak (Quercus calliprinos). These insects were used as a red dye since antiquity by the ancient Egyptians, Mesopotamians, Indians, Greeks, Romans, and Iranians. The kermes dye is a rich red, a crimson. It has good colour fastness in silk and wool. It was much esteemed in the medieval era for dyeing silk and wool, particularly scarlet cloth. Post-medievally it was replaced by other red dyes, starting with cochineal.
Kermes ultimately derives from the Sanskrit word कृमिज or kṛmija meaning "worm-made". This was adopted into Persian and later Arabic as قرمز qermez. The modern English word kermes was borrowed from the French term kermès.
Kermes dye is of ancient origin; jars of kermes have been found in a Neolithic cave-burial at Adaouste, northeast of Aix-en-Provence. The early Egyptians made use of the kermes dye.
In the Middle Ages, rich crimson and scarlet silks dyed with kermes in the new silk-weaving centers of Italy and Sicily exceeded the legendary Tyrian purple "in status and desirability". The dyestuff was called "grain" (grana) in all Western European languages because the desiccated eggs resembled fine grains of wheat or sand, and textiles dyed with kermes were described as dyed in the grain. Woollens were frequently dyed blue with woad before spinning and weaving, and then piece-dyed in kermes, producing a wide range colours from blacks and grays through browns, murreys, purples, and sanguines. One source dated to the 12th-century notes that kermes dye adheres best to animal-based fibers (e.g. wool, silk, etc.), rather than to plant-based fibers (e.g. cotton, linen, etc.).
By the 14th and early 15th century, brilliant full grain pure kermes scarlet was "by far the most esteemed, most regal" colour for luxury woollen textiles in the Low Countries, England, France, Spain and Italy.
Following the Spanish conquest of the Aztec Empire, Mexican cochineal, which produced a stronger dye and could thus be used in smaller quantities, replaced kermes dyes in general use in Europe.
The English word for the biblical scarlet (Exodus 25:4, et al.) is merely a literal translation taken from the Koinē Greek: κόκκινον = kókkinon, as found in the Septuagint (LXX), meaning, "scarlet." By an analysis of the English word alone, unlike the original Hebrew biblical text (tola'at shani), it is not readily understood that the scarlet color is derived from a living organism. The source of the color being derived from a "living organism" is explicitly stated in the Jerusalem Talmud (Kila'im 9:1 [32a]), and is implied by the name tola'at = "worm," or "worm of scarlet," and which the ancients in the Roman world only knew as grani coccum = "the grain of the scarlet yarn."
Scarlet was one of three principal pigments used in the Temple curtain, appurtenances, and sacred vestments, etc. for a total of five basic colors: gold, blue, purple, scarlet and white. Threads of each color were twined together to form thick yarns (the golden threads being pounded and cut from sheet metal, while white was the natural, bleached linen; the others made from either wool or silk yarns that had been dyed with various pigments). The curtain was skillfully woven together in a loom to make winged cherubim motifs, etc. Scarlet-dyed yarn was also thrown as an adjunct into the burning ashes of the Red heifer, as was it used as an adjunct in the purification ritual of lepers who had been healed.
While production of the crimson or scarlet dye from the kermes scale insect had, traditionally, been an art preserved with medieval dyers, the practice seemed to have been lost for many centuries. Late exponents of Jewish law were baffled by what was meant in the compendium of oral Jewish law, the Tosefta (Menachot 9:16), when it stated that the tola'at shani, or scarlet colored wool, may only be utilized from the tola'at (worm-like aphid) which abounds in the mountainous regions, for the preparation of the dye used in the priests' girdles (Hebrew: avneṭ). The dye's crimson or scarlet-orange tinge is alluded to in an early rabbinic source, Pesikta Rabbati, where tola'at shani is said to be "neither red, nor green," but of an intermediate color. The 10th-century biblical exegete, Saadia Gaon (882–942), opines that the scarlet colored fabric was qirmiz (Arabic: قرمز), derived from the kermes insect and which produced a color ranging from Venetian scarlet to crimson. According to Saadia, the dye was applied to silk yarns. A rare 10th-century Arabic document was retrieved by the Department of Land of Israel Studies professor, Zohar Amar, from which he was able to reproduce the dye extract, using antique methods.
Out of the four kermes scale insects tested in Israel, the wingless female Kermes echinatus with her unhatched eggs still in her body yielded the brightest red colorant. The scale insect is first dried and ground to a powder. The dyestuff is then placed in a pot of water and cooked on a low heat, which turns the water red. The water is then strained and is ready for use. Those familiar with the dyeing technique have noted that before inserting the fabric into the bath containing the dye solution, the fabric is first dipped into a bath of dissolved alum, which, when added to the dye solution, gives to the fabric its bright reddish-orange color, besides serving as a mordant. Darker shades are achieved by repeating the dyeing process several times, having the fabric dry, and re-dyed.
According to field research conducted by Amar and colleagues, the female K. echinatus insect, which has a camouflage color of grey to reddish-brown, "produces the dye pigment in both her body and in her eggs, only at the peak of her adulthood, which continues for no more than one month, around July and August." A delay in harvesting the scale insect with eggs may result in a significant reduction in dye production. After collecting, the insects are first dried in the shade for a period of one week, ground to a powder, and then steeped in water for 45 minutes and which maintains a low-heated temperature of 60 degrees Celsius to 80°C (140° Fahrenheit to 176°F). To this hot bath is added the fabric to absorb the dye. Heating the dye solution to a temperature more than this is liable to destroy the pigment or to cause fading. When alum is added to the dye substance as a mordant, a bright red-orange hue is obtained, which color is then made color-fast.
Chemical analysis of the dye extract shows a high percentage of kermesic acid (C16H10O8) (Ka; maximum at 480 nanometers [nm]) and flavokermesic acid (Fk; maximum at 432 nm). Wool dyed in an acid bath solution with kermes produced a red-orange hue, but without the acidic addition the color remained a brick red or dark red. Other acid bath solutions produced a golden-yellow hue.
Amar found that the host trees in the Land of Israel (viz. Quercus calliprinos) produced varied sizes of the scale insect Kermes echinatus, the largest of which being found in Israel's north, particularly in the Upper Galilee region and in the northern parts of the Golan Heights, which reached a mean size of 6.4–5 millimeters. However, the scale insect's distribution was not uniform. Some trees were effected by the parasites, while others were not. 1 kilogram (2.2 lb) of freshly harvested kermes scale insects loses about two-thirds of its weight when dried. The dried dyestuff is sold either in its raw form as kernels, as powder, or as briquettes. Approximately 50,000 to 60,000 scale insects are needed to produce one kilogram of the dried dyestuff.
Scarlet (crimson) features prominently in ancient Hebrew lore:
Though your sins are like scarlet, they shall be as white as snow; though they are red like crimson, they shall become like wool. – Isaiah 1:18
Other accounts mention scarlet as being one of the chief colors used to decorate the bridal chamber in Jewish weddings, wherein they would hang large colored sheets:
What are they 'the bridal chambers'? They are [the rooms fitted with wall-hangings of] scarlet overlaid with gold. – Tosefta (Sotah 15:9)
During the Second Temple period, the annual Jewish ritual of the Day of Atonement (Yom Kippur) required that a man would lead away the scapegoat and, when he reached a precipitous ravine some distance away, he would tie scarlet (crimson) thread to its horns, before pushing it down unto its death:
He divided the thread of crimson wool and tied one half to the rock and the other half between its horns, and he pushed it from behind; and it went rolling down. – Mishnah (Yoma 6:6)