Naomibbbb

I want to use manganese wash on white stoneware clay after it has been bisque fired to tint the clay slightly more tan/brown and after use a clear glossy glaze and use manganese as well as other oxides on top of that glaze- does anyone have experience or knows what would happen if oxides are applied under as well as over a glaze? Will these interact or will they not due to the glaze between?