Abstract: Naturally occurring bauxites are suitable as flame retardants and can be incorporated into polymeric carpet backings, when they are ground or pulverized to obtain a generally uniform distribution of particles predominantly less than 250 micrometers in size and containing up to 45 wt. % of fines (less than 3 micrometers in size), and then used in combination with an appropriate wetting agent, dispersant, froth aid, latex, and thickener package to wet-out and disperse the particles and provide adequate control of viscosity build. The bauxite should preferably have a high gibbsite content and should preferably have a pH range of from 4.5 to 8. Mechanical stirring can be used to aid in viscosity control. Lowering the specified percent solids in a formulation by adding small amounts of water allows for even finer ground bauxite (up to 55 wt. % of fines) to be used as filler for carpet backings.