This is a vintage peach luster mug with the initial "G". There is no maker's mark on the bottom but it is white glass. There is wear to the interior peach glaze from use and some dulling to the rim from use where it was used. The peach color is intact it is just less shiny at the rim. Measures about 3.5" high and 3 1/4" across the top. Note that lusterware is difficult to photograph without glare and other effects because of the shine.