Resumen
This paper describes the identification of dyes on fifty yarn samples from a tapestry created by the well-known 17th-century Flemish workshop of the Mattens family. The design of the tapestry is based on the first of ten drawings known as the Acts of the Apostles by the famed 16th-century Italian painter Raphael. The drawings were commissioned by Pope Leo X and translated into tapestries by Pieter van Aelst; these original tapestries are still in the collection of the Vatican Museums. The present work was reproduced over a century later from the original drawing and is one in a possible set of nearly fifty known copies of the original tapestry cycle. Most of the Mattens yarn samples were found to be dyed by weld, indigo, and madder, as well as a few using brazilwood and lichen, but no insect dyes were detected. A significant finding in the present study was the detection of the dye component pseudoindirubin 1, alongside indigotin and indirubin, as well as yarns that only yielded the latter two dyes. The implication of using this new marker as objective evidence of the use of both woad and most likely Asian indigo is explored. The historical and conservation significance of the dyestuffs identified is also discussed.