Two ceramic or sapphire pieces are welded together using a plasma torch that includes a cylindrical vessel having first and second ends, a tangential inlet connected to or proximate to the first end, a tangential outlet connected to or proximate to the second end, an electrode housing connected to the first end of the cylindrical vessel such that a first electrode is aligned with a longitudinal axis of the cylindrical vessel, and extends into the cylindrical vessel. A hollow electrode nozzle is connected to the second end of the cylindrical vessel such that the center line of the hollow electrode nozzle is aligned with the longitudinal axis of the cylindrical vessel. A second electrode is positioned proximate to the hollow electrode nozzle. The two ceramic or sapphire pieces are placed between the second electrode and the hollow electrode, and are welded together with the plasma exiting from the hollow electrode.