It is Valyrian steel, and said to have a black blade.
Ser Jon Roxton wielded the blade during the Dance of the Dragons fighting for king Aegon II. During the Battle on the Honeywine he used it to deliver a fatal wound to Lord Owen Costayne. During the Second Battle of Tumbleton, "Bold" Jon slew Hugh Hammer when he least suspected it, splitting him from groin to throat with Orphan-Maker. Shortly thereafter he was killed by Hugh's men in a ten against one fight.