I use Highwater Raku clay for my sculptures because I like the workability of it and I occasionally pit fire. I'd like to make a teapot that is both sculptural AND functional for an invitational teapot show. After 2-days of hair-pulling frustration, I'm halfway through making a sculpture that gives every indication that it will be a functional teapot -- BUT it just occurred to me that raku clay may be inappropriate for a functional piece. If I fire it at its maximum temperature, cone 6, would it be non-porous? It wouldn't need to be every-day functional; if the future buyer uses it at all, I'm sure it would be on very rare occasions because my teapots are not exactly ergonomically designed! (see pix of last two failed attempts at function). So -- do I switch to another clay or keep going with this one?