Caesalpinia sappan by BioDivLibrary on Flickr.
"This plant has many uses. It possesses medicinal abilities as an antibacterial and for its anticoagulant properties. It also produces a valued type of reddish dye called brazilin, used for dyeing fabric as well as making red paints and inks." (source)
See also: “Caesalpinia sappan A medicinal and dye yielding plant” (pdf)