The invention provides a block splitter assembly comprising first lower and second upper opposed splitter blade assemblies. The splitter blade assemblies have a splitting blade and two or more first forming blades. One forming blade is disposed to the right of and one forming blade is disposed to the left of the first splitting blade. The forming blades have forming edges. The splitting blade has a splitting edge that is straight, and the splitting blade has a greater maximum vertical dimension than the maximum vertical dimension of the forming blades. The splitting edge of the first splitting blade is opposed to the splitting edge of the second splitting blade.