Abstract: A building block for erecting walls, houses or other buildings is provided. The block is made of a special mineral mixture and has at least two relatively parallel channel type hollow spaces passing therethrough. The hollow spaces of the building block are defined by can shaped metal or synthetic plastics profiles. Also a mold with longitudinal and face walls is provided, in particular for producing such a building block. The mold has a frame shaped construction of angle pieces and is arranged on a working plate.