Copper Peptides GHK Cu Beef Tallow for Skin: Blue Balm with Methylene Blue, Manuka Honey & Vitamin E Natural Face and Body Moisturizer for Mature, Dry & Sensitive Skin 2oz Ward What make blue? . The blue color of GHK Cu is due to the copper ion mineral bound with the peptide. The binding occurs through the donation of electrons GHKCu Copper Peptides: Clinically Proven Collagen & Skin Regeneration Power Scrub a lil Deepa Copper Peptide Serum with 1% GHK Cu peptide, Argireline and Matrixyl 3000