A procedure for manufacturing artificial sands in all color range (Machine-translation by Google Translate, not legally binding)

摘要

Process of manufacturing artificial sands in all the ranges of colors, characterized in that high-quality artificial cements are used, essentially the whites and special colors of oxides for cements, mixed in suitable proportions to obtain the tonalities that are desired, adding to them a minimum amount of water, which allows mixing to get a paste, which will extract the air by subjecting it to the action of vibrators. (Machine-translation by Google Translate, not legally binding)