Jennie and I have some fun events coming up including a raku firing and a salt firing. For these firings, we have to throw with a different sort of clay than our usual cone 6 (cone designates the temperature, ie. cone 10 is much hotter than cone 04, etc.). I decided to mix in some "tailings" from the North Shore of MN. These tailings have all sorts of minerals in them which, I'm hoping, will produce wonderful effects in the firings. They give the raw clay a little umph and show through the glazes I'll choose.
A raku firing is a lot of fun because it is so involved and pretty fast. Basically, a raku firing involves putting a pot into a small kiln and heating it until it is red hot. Then a potter grabs it with tongs, takes it out, and places it inside of a trash can full of sawdust and other combustible material. Of course, these things burst into flame and the potter quickly covers the trash can with the lid, blocking the flow of oxygen and letting the pot smolder. As soon as the interior has calmed a bit, the pot can be taken out and placed into water where it finishes cooling and is washed off. The rapid cooling of a red hot pot crackles certain low fire glazes, like you see in the pot to the left. Usually, if you see a pot with what looks like black clay, it is actually raku fired. The process turns the raw clay a pitch black color.
For these firings, the whole involved process shows in variations on the pots. Because of that, anything that casts a shadow on a pot (like adding clay, cutting into it, pushing into it, changes of direction in a pot's composition, etc.) really show off the best of the best from the atmosphere of the kiln. See the difference in the two pots below for clarification on what I am talking about (and each has its place... just notice the differences):