Originally Posted by greenman857
I use a stoneware that I bought commercially. most clays are fine, the only problem might be if unusual refractories (helps the clay "melt" at a certain temp) for really low-fire they add some weird stuff that may not be good for an aquarium. But all in all the stuff has to be non-toxic for food consumption for humans and so is safe for aquariums.
Pottery is frequently fired (baked) twice, once at a lower temp (bisque) and then higher temp (glaze). The glaze firing actually causes the clay to fuze into a glasslike substance (stoneware or porcelain)
My theory is you only want to bisque it because its more porous and as such harbors micro-organisms in its body which could act as a filter of sorts.
High fire is more like glass or a quartz rock.
Plus its quicker and cheaper just to fire to bisque.
Here's a couple of pieces I have kicking around.
Now thats what I would like to do. Very nice looking work, Im thinking the sharpie is for size reference or do you use it to shade the peice? How did you get the color, and shading so perfect?