Abstract: The invention provides block forming apparatus with a compression chamber having upper and lower opposed ends, and defining a common inlet and outlet at the upper end of the compression chamber, via which the compression chamber can be charged with block forming material, and via which a formed block can be ejected from the compression chamber. The compression chamber is mounted pivotably on a frame so that it can be pivoted sequentially through different positions. A lower ram is movable between an extended position, to compress the block forming material from the bottom, and a retracted position. An upper ram is movable between a retracted position clear of the common inlet and outlet, and a closed position. A set of actuators move the compression chamber between a first, loading position, a second, compacting position and a third, ejection position.