Toyo Grape Box

The material this box is made from is a mystery. At first I thought it was soapstone, but now I am just not sure. It almost has a porous look to it, but it is not plastic or wood. Anyway, it is covered in a grape and vine design. It is 6 1/4" in length, 5" in width and 2 3/4" in height. It was manufactured in Korea. There is minor wear to the finish and a small shallow chip on the bottom rim. Please email for additional photos and maybe you can help me identify the material. I need your zip code to calculate the postage.