Casting a lightweight reproduction: duoMatrix™ NEO is a polymer modified gypsum system that is perfect for casting strong yet lightweight architectural elements. It is mixed 100 Parts A (powder) to 50 Parts B (liquid). Using a drill mixer, combine the powder with the liquid and mix thoroughly, pausing occasionally to scrape the sides and bottom of the container. Once thoroughly mixed, pour the mixture into the mold. This first batch will be used to make a ''gel coat'' on the surface of the mold. Brush the gel coat over the surface of the mold to create a thin layer of duoMatrix™ NEO.