One of my patients has shared this picture with me as she felt it was odd that this peptide had this very vivid blue colour, while her other peptides had a clear Advanced GHK Cu Neck & Face Serum Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with Buy GHK Cu 50mg Peptide COA Verified UK