User blog comment:TESClaymore/Skyrim Answers from Bethesda/@comment-3097746-20110831120104/@comment-4043978-20110902212143

Slightly less than the truth. Ebony is actually blackened steel. But in the sense that it is steel it is very highly reinforced and such. It DOES resemble obsidian, minus the shininess. Obsidian is a glass-like Igneous rock is it not? Maybe Metamorphic......