Composimold composistone 1lb 454g composimold cmcs1 p this composimold composistone is harder than plaster yet still smoother than cement making it ideal for lawn and shelf ornaments sculptures craft parts and other general applications the plaster cement system uses a dry mix and water at a ratio of 2 5 parts powder to 1 part water and not less than 2 parts powder to 1 part water by weight or volume p p mixing br measure between 2 2 5 parts dry mix to 1 part water by volume into