New Clays, Class assignment #7

This quarter I've been working with clays that I am unfamilar with.  Instead of the "tried and true" Tokamari Porcelain I've been working with "Kleiber"  porcelain and I've also been working with a dense, white earthenware clay called "JG".  Both clays are available at Tacoma Clay Art and both were suggested by the staff there.

Kleiber works well for slab construction, though the description in Clay Art catalog lists it as ideal for wood firing.  JG fires at cone 10 a bit more glassy than Tokamari, which is want, and it's no more difficult to work with Than Toka.  I think it responds well to our shop cone 10 glazes and makes them a bit more glassy also, but no so much that it is a problem.  For example, if you apply the same amounts of Korean Celedon to both clays in the same kiln it will be a bit bluer and a bit more glassy then on Toka.  I don't get the idea that Kleiber would "let loose" and stick to shelves or start melting down a few cones higher so there is no danger that this is "too close" to melting down at cone 10.   I will continue to work with it to finish off the 50 pounds I picked up last summer.

The "JG" earthenware (cone 06) clay fires white at bisque (both bisque and finished glazes fire to cone 06).   The "working properties" of JG are similar to Toka.  It dries quickly, slakes quickly when exposed to water or slip, and handles and attachments are prone to cracking if you hurry it.  If you made two identical cups (for example), one of Toka and one of JG, you might not know there is a difference except that the JG is a bit browner of course, though it bisques to a nice white.  I'll be working on "Imari" themes with the JG pieces, using black and red Iron oxide stains and also Cobalt oxide and Carbonate and will post those pieces when I start to get finished products (look for an update to this post, IF i can figure out how to edit it.

This quarter I have also completed several "Dakota Red Clay" jars, a drum, and a sculpture.  I always learn from each jar and hope my pieces are getting more organic. The clay drum, a smaller piece was interesting in that I started from the bottom up and built it all the way to the top (instead of constructing two halves and attaching them).  I will smoke fire the two jars this month when the shop does a raku firing.  I also plan to Raku two JG cups to see how this dense earthenware clay responds to the shocks of raku, no reason it won't make a good Raku body, though it will no doubt be a bit more fragile than grog laden clays mixed specifically for the Raku process.

The three photos attached to this blog show the variety of forms that can be created from one clay, in this case Tokamari.  Hopefully in a few weeks I can contrast the firing and glazing properties of Toka to Kleiber.  The small bowl below was fired in the Raku kiln.