Faux Onyx Brooch

I can't find a makers mark. The large center stone is probably plastic/lucite and the accent black stones are glass. I am assuming the seed pearls are fake. It is approximately 1 3/4 inches. There are no missing stones, the fastening mechanism is secure and there does not appear to be any damage to the finish. Additional detailed photos are available. I need your zip code to calculate the postage.