The materials used for the production are Quarry Dust and Sandcrest. We produce the following building blocks: A. 400mm x 200mm x 100mm (4 Inches) B. 400mm x 200mm x 125mm (5 Inches) C. 400mm x 200mm x 150mm (6 Inches) D. 400mm x 200mm x 200mm (8 Inches) The designs are available in both solid and hollow. However, we are not limited to these ...