This is amazing. Adam Field has been studying with onggi masters in Korea. Check it out.
I also like his music choices on his videos.
From the youtube comments section:
Just in case you missed it in the comments:
"-the wall is 1/2 inch near the rim & foot & 1/4 inch at the belly"
Go read that sentence again, I'll wait.
Check out some other videos at Adam's website.