The parent commenter may be thinking this wok is carbon steel, which is silvery to start with but must be seasoned (which is to say, allowed to heat up with oil on it to form a nonstick layer). You can easily tell a seasoned carbon steel pan because it has the black look of cast iron, another type of pan that is seasoned.

Whether the pan is actually carbon steel or just stainless that has some accumulation, I don't know.