Asian oriental antique 4 ft tall thai buddhist woman/goddess statue

I have an acquaintance from Vietnam who said that she was sure it was Thai. I think that it's a buddhist goddess, but I suppose it could just be a Thai woman. It's obviously handmade (at least the gold colored part). It's made of some kind of metal (both the black part and the gold part) and is hollow inside. She still ways about 40 pounds though. I've been unable to find any kind of artist's mark on it. It looks like it's been kept outside in the past, because there are a few small spots of corrosion. Anything that anyone could tell me would be much appreciated. I don't really know the first thing about it!