PatoMark is used by surgeons and pathologists to permanently mark the margins of tissues to aid in the orientation of tissues and aid in diagnosis. Patomark dyes are opaque in nature and adhere to tissue surfaces very effectively. The colors were selected to avoid confusion with routine histological stains. The viscosity allows the application of an even, thin coat ink which penetrates the tissue surface enough to allow it to remain visible through tissue processing. Acetone or Vinegar can be used to fix dye to tissue.