GHK CU: How to Mix It The Peptide Report Just started GHK Cu? Here's what to expect This isn't an overnight peptide, it builds Weeks 12: You may start noticing small shiftsskin feels a bit smoother, nails a little stronger Weeks 34: GHK Cu Peptide Regenerative & Cosmetic Research Amazon.com: GHK Cu Copper Peptide Powder 99.7%+ Pure Cosmetic Grade Ingredient for DIY Serums, Creams & Scalp Tonics Supports Collagen & Fuller Hair (1g) : Beauty & Personal Care A GHK Cu face serum appears blue because the active ingredient, GHK Cu (copper peptide), is naturally a blue colored powder, meaning its inherent color transfers to the serum when mixed in; this blue hue Cu Peptide Before and After: What to Expect for Skin and Hair