a precious metal structure which has an internal gas permeable membrane is described herein for a glass manufacturing vessel configured to have molten glass flow therein . the internal gas permeable membrane can be supplied with an atmosphere of gas to control the flux of hydrogen into our out of the molten glass or otherwise improve the production of the molten glass . in this manner , the undesirable detrimental reactions that can occur at the interface of the molten glass and precious metal interface which can cause defects in the molten glass such as bubbles or solid inclusions can be stopped or at least substantially reduced .