Copper tripeptide (GHK Cu; Copper Glycyl histidine tripeptide) CAS 89030 95 5 AbMole BioScience Copper tripeptide Price 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: The Elegant Copper Peptide for Skin and Scalp Renewal Renew Vitality GHK Cu 50mg Copper Tripeptide Research Compound 99%