the invention provides a composition that significantly shortens the time necessary to produce a ceramic shell mold . the composition of the invention is used to produce a shell - mold for the investment casting process , providing decreased processing times by reducing the number of shell dips , and better handling and dewaxing through increased green strength . the invention provides a method of forming a shell mold , comprising providing an investment casting shell - mold composition comprising 0 . 1 to 70 percent by weight inorganic fibers , a binder composition comprising a mixture of 20 - 98 percent by weight of a colloidal sol comprising particles , and 1 - 20 percent by weight organic latex polymer .