To get familiar with the material and the production technique I made 27 specimens. I was weekly examining the specimens weight and volume. It gave me information on how the density, the shrinkage, and the relative weight loss, relate with the proportion of each material in the mix. I made 3 series of experiments. As the forms, the production process and the proportions became more accurate, the deviations between the same specimens became smaller, and the results were safer to use. The block΄s size is 15x15x15 cm, the standard size of testing concrete specimens.