Words cannot describe just how stoked I am to see this here. My imagination made real more true to my vision than I'd dared hope.
This is featured in some fanfic I am working on, which is already FAR to long to post on a forum. But as Darkmatter says, it used to be an Imoerial Knight's saber.
Briefly: in Legends, Legacy era...The Imperial Knight known as Eshkar Niin turned to The Dark Side and thus ensued a battle between him and his once apprentice: Drako. Drako defeated his former master believing him to be dead. However the Knight turned Sith had deceived Drako and survived to appear once more as Darth Havok.
When we see his return as a Sith Lord, Havok carries a black coral lightsaber with a red blade. His old saber having been lost in that duel upon the rooftops of Bastion.
In my fanfic, a young Jensaarai warrior is drawn to it, finding it decades later in low orbit around Bastion, all but ruined by the corrosive effects of radiation, space dust and toxic waste of military industry.
Hence the corroded emitter and pommel. The outer shroud has gone completely to show the inner workings (greeblies-excuse!) but has now been fitted with a nice new Sith-like shroud.
The enscription is in Kittat, aka Old Tongue which is the Sith language used for incantations etc. It says "summon demon", an except from a partly translated document that you can find online.
And thus this saber is names Havok's Ember, after "darkest ember" which is one of the other phrases that was translated in that document.
This is so like what I had in mind that I feel rather emotional to see these pics with the incredible work on the emitter, the lovely greebles and weathering alongside a glowing red that mimics the red of Imperial Knight's armour, plus the forked shroud in reference to Havok's Iktochi horns.
The inlaid wire around the corroded switch really sets it off!
I can only thank you Darkmatter for being the right kind of crazy and for all your painstaking work