its molten glass contacting surfaces with a thin base coating of a nickel chromium aluminum cobalt yttria composite powder and a somewhat thicker coating of a prealloyed ceria yttria stabilized zirconium oxide superimposed on the base coating application_number US 74197900 A description an orifice ring according to the present invention is identified generally by reference numeral 10 in fig1 the orifice ring 10 is made up of a ceramic element 12 which may be of conventional construction and is designed to be used at the outlet of a molten glass feeder bowl that is used to provide molten glass to an i s glass forming machine through openings 14 16 in the orifice ring 10 thus the orifice ring 10 is submerged in molten glass during its useful life with its upper surface in contact with the molten glass the ceramic element 12 of the orifice ring 10 is provided with a superimposed pair of coatings 18 20 on each of its glass contacting surfaces the innermost or base coating 18 is a coating that is made up of nickel chromium aluminum cobalt yttria composite powder that is applied to the ceramic element 12 to an approximate thickness of 0 002 in by plasma spraying and metco.