The Coronation Mantle of Roger II of Sicily, silk dyed with kermes and embroidered with gold thread and pearls. Royal Workshop, Palermo, Sicily, 1133–34. Kunsthistorisches Museum, Vienna.
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 insects live on the sap of certain trees, especially Kermes oak tree near the Mediterranean region. The English color names crimson and carmine are derived from the word kermes, and many other languages have a word for "red" that is derived from kermes due to the widespread use of this dye in medieval times and the rich red color that it yields. The dye is of ancient origin; jars of kermes have been found in a Neolithic cave-burial at Adaouste, northeast of Aix-en-Provence.
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" 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 colors from blacks and grays through browns, murreys, purples, and sanguines. By the 14th and early 15th century, brilliant full grain pure kermes scarlet was "by far the most esteemed, most regal" color for luxury woollen textiles in the Low Countries, England, France, Spain and Italy.