Abstract: A cement-type binding material suitable as a building material for use in the manner of a Portland cement including for underground work, or as a curing accelerating additive in mortar cement or masonry cement or in concrete or as a basic material for producing building components, is produced by mixing flue dust or flue ash with a product obtained by desulfurizing flue gases. The quantity of flue dust or ash is so measured than any free lime and lime being freed during an oxidizing and calcining treatment is completely bound to aluminates and silicates capable of reacting with water. The so produced intermediate multi-phase product is milled to a certain fineness and mixed with slag sand also milled to a certain fineness. The so obtained product is suitable for use in all instances where gypsum could not be used heretofore or could be used only under expensive protective measures.