We have Obsidian Armor so why not Obsidian Weapons?
I guess it would cost 15k + materials and at that price it has to be fully customizable and give the look for each class. For an Ele, it has the obisidian look in the outpost but in the field it can burst into flames (or dust, lightning, dry ice). It has to look animated (you know that it has to be animated out the yaya), match the armor (if your armor has spikes then the weapon should have spikes somewhere) and be the weapon of choice since its Obsidian.
Dunno, just wondered why my, uh, wooden staff doesn't fit with my obsidian armor.
Side note: shouldn't the text on Obsidian Armor be a different color? annnnnnnd shouldn't it receive an extra benefit other than looking cool? (the latter has been requested for quite some time and since prices are dropping so everyone can afford it, now is a good time to look into it)