Langridge oxidising Patina (Activator) is used to activate your Rust or Verdigris finish, simply apply Oxidising Patina and wait. The longer the patina stays wet, the stronger the reaction and brighter the final colour. Timing guides the effect: approximately 45 minutes on Rust Base produces a deep red rust, while 90 minutes creates a bright orange-yellow tone. Experiment with application time to achieve your desired finish.