xylindein

Century Dictionary and Cyclopedia

1. n. A blue compound contained in green, decayed wood which has been infected with Peziza æruginosa. It crystallizes in quadratic plates which have a strong coppery luster.

Wiktionary

1. n. A quinone pigment, a dimeric naphthoquinone derivative, responsible for the characteristic bluish-green stain of wood infected by the Chlorociboria aeruginascens mushroom.

GNU Webster's 1913

1. n. A green or blue pigment produced by Peziza in certain kinds of decayed wood, as the beech, oak, birch, etc., and extracted as an amorphous powder resembling indigo.