Bright skin Suppositories Lightening & Brightening of the Skin Glutathione Skin Brightener with Ceramosides NOW Foods Bright skin Suppositories Lightening & Brightening of the Skin Your copper peptide product should be this exact blue. If it isn't, you already have your answer. GHK Cu is blue because of coordination chemistry, not dye. The Cu ion at the center GHK Cu Peptide The benefits, side effects, and more [2026]