Also called aluminum trihydrate, this material is a translucent filler used extensively in clear polyester for making cast marble and onyx. By adding a little white pigment to a mixture of this material and clear polyester resin, one can make a pretty good faux marble casting. Hydrated alumina is also a fire retardant filler.
*the picture shows a 10 lb. bag, but this SKU is for 5 lbs.
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