American Marble MANUFACTURING PROCESS Cultured marble is a mixture of polyester resin (an oil by-product) and limestone (quarried out of the Salinas Hills). A mixture is made up and poured into molds much like concrete. We mix the product by pouring the resin (looks like syrup) into a dough mixer. We add a chemical hardener and then add titanium (in a powder form) to make the product whiter. Then we add the limestone and mix this for several minutes. Then we put the marble, color and tint on top of the batch while it is sitting in the dough mixer. This will be the veining in the marble. This batch is poured by hand into molds that have been previously sprayed with a clear gel coat. The gel coat is 20 mils thick and protects the product from staining. The product bonds to the gel coat and hardens in a few hours. We remove it from the molds the next day. The edges are ground and the product is buffed. It is then ready for installation. Cultured onyx and granite are made much the same way with a few minor differences.