You know I love my Color Cubes, but these gorgeous old Mosaik blocks give them a run for their money; just gorgeous! I have searched a bunch and not found another set like these (I would buy them up if I could find them), which I believe are German (the torn bottom left corner of the box I would guess says Hamburg); though I can find no reference to Ernst Gravenhorst anywhere. At any rate, the rich, glossy painted colors are fantastic, and as with color cubes, it is pure joy to lose time arranging and rearranging these, which look fantastic anyway you put them. Super.
The box is pretty tattered and missing a side, but still holding together. The blocks themselves are in good shape, with wear most visible on two of the yellow triangles, which show some darkening to their surfaces. Box measures Box measures 5 1/4" x 5 1/4" x 1/2. A triangle block measures 1 3/8" on each short side and 2 1/16" on the hypotenuse.