CASTWORKS (formerly Plasterform) is a premier manufacturer of architectural products, specializing in the design and production of custom architectural castings. Explore the endless number of options using materials such as GFRG, GFRC, FRP, and Interior Molded Stone. Glass Fiber Reinforced Gypsum (GFRG/GRG) is a lightweight interior material that is commonly used for column covers but can also be made into just about any shape imaginable. Recreate the look of natural stone with interior molded stone composite. Glass Fiber Reinforced Concrete (GFRC) is lightweight and ideal for architectural details, from friezes and finials to pediments and rainscreens. With unmatched flexibility, Interior Molded Stone offers unlimited possibilities for interior castings, large or small, to complement your design.