An Etymological Dictionary of the German Language/Annotated/Glanz
Glanz, masculine, ‘lustre, splendour,’ from the equivalent Middle High German glanz (wanting in Old High German), with which is connected the Old High German and Middle High German adjective glanz, ‘bright, shining’; Modern High German glänzen, from the equivalent Old High German and Middle High German glęnzen; to the same class belong Middle High German glander, ‘splendour, shining,’ and glanst, ‘splendour,’ further glinster, ‘splendour,’ and the very rare strong verb glinzen. A stem glint- is wanting in the rest of the Teutonic dialects unless the cognates of glatt (Gothic *glada-) are allied.