When referring to local cultured marble dealers and synthetic marble dealers, consumers should understand that there is really no difference between the two. The use of the terms synthetic and cultured are interchangeable depending on who you are speaking with. Any local cultured marble dealers or synthetic marble dealers will be carrying roughly the same product. Cultured marble is what we refer to as a composite product. The marble is composed of a high percentage of actual limestone dust, which is then blended with a hard polymer plastic and formed under pressure into the final product, normally kitchen and bathroom counter tops with molded sinks. The versatility of the material makes it an excellent substitute for genuine marble, since there is no way to form real marble, making built in sinks an impossible option with the genuine stone When the forming process is complete, the resulting marble counter top is then treated with a gel coat, which is similar to the final finish on your car, but many times harder and more durable. This gel-coat helps to protect the counter surface from stains and discoloration.