Fig. 3From: Island blues: indigenous knowledge of indigo-yielding plant species used by Hainan Miao and Li dyers on Hainan Island, ChinaIndigo extraction method of Indigofera tinctoria by Li dyers. a Removing the rotten aerial parts from the the extraction vat. b Filtering the lime powder. c Agitation for oxygenation. d Sedimentation on the bottomBack to article page