Can be applied onto wet grout, stone, chalk, lime surfaces or aged cement. Shelf-life: approx. 12 months. Protect against frost. For interior and exterior use. Dilute 1 part of potassium silicate with 2 parts water, add about 5 - 15 % finely ground quartz powder (e.g. 58610) and add up to 5 % of any pigment (suitable in water glass). Stir well. Does not work well on flaking paint. Please make tests before application.