Abstract: 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.