The study investigates questions and considerations emerging when stone in historic buildings needs to be replaced. The focus is on the surface treatment of stone in sandstone façades in pre-industrial buildings. That means buildings constructed by traditional methods and craftsmanship without the use of modern technology.The research issue originates from the extensive stonework that is planned for the façades of the Stockholm Palace. The project includes the replacement of large quantities of damaged stone to newly cut stone. This raises the questions about the use of modern and rational methods for surface treatment on the replacement stone.