Abstract: A sample holder for use in a mass spectrometer is provided for heating a sample to discharge ions through an electrostatic field which focuses and accelerates the ions for analysis. Individual specimen holders form a plurality of filaments for heating the sample materials for ion emission. Mounting devices hold the plurality of filaments at regular spaced apart angles in a closed configuration adjacent the electrostatic field elements. A substantially solid ceramic turret is provided with a plurality of electrical contacts which engage the individual holder means for energizing the filaments and forming a corresponding plurality of radially facing, axially extending first conductive surfaces. A substantially solid stationary turret bearing member is mounted about the rotating turret with a plurality of radially biased second electrical conductive surfaces, mounted to electrically contact facing ones of the plurality of radially facing first conductive surfaces.