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 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 COPPER TRIPEPTIDE GHK AGE REGRESSION.COM Copper Peptide (GHK Cu) Supplier Cosmetic Ingredient for Formulators Creative Peptides