<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">archil</topic></authority><related type="other"><topic>lichens</topic></related><related type="other"><topic>French purple</topic></related><related type="other"><topic>orcein</topic></related><related type="broader"><topic>vegetable dye</topic></related><variant type="other"><topic>cudbear</topic></variant><variant type="other"><topic>orchil</topic></variant><variant type="other"><topic>red indigo</topic></variant> <note xml:lang="en"><![CDATA[ A natural dye that is bright red to rich purple color, obtained from any of several lichens; used as a pigment, textile dye, wood stain, food colorant, and an indicator dye that turns blue in alkaline solutions. It was by the ancient Egyptians; the preparation was rediscovered by the Italians and used to make the brilliant red and purple Florentine cloth. In the18th century a Scottish chemist C. Gordon patented the process, which he called "cudbear." The dark red color in archil is formed when lecanoric acid is converted to orcein by fermentation then oxidation.  ]]></note></mads>