As you can see from this lovely chart (made by delamore, I believe?)
http://i36.tinypic.com/jv6qkk.jpg
You can see that quality of items (kiln -> bricks -> forge, ginery or crucible.... which lead to quality of metal item quality) can be bogged down by the quality of clay you use.
Perhaps there is a way we can make clay through crafting (soil + water) to boost the quality?
Or make our own claypits (200 soil, 100 water) which over time rise in quality?
Just throwing out an idea.