Friday, March 20, 2009

Bowl.

Firstly, I apologize for the quality of the photo. I'm using my web cam. as I still have not bought a new camera, and the old Canon is definitely dead(it did find new legs for a while). 
I will replace the bad photos when I get a new camera. 
This was the bowl that grabbed my attention from the last firing, it has rarely left my side for the past two days. It has a slashed indentation down the front, with a raised badge at the top. The brown ring is an iron oxide brush line.  
Inside are a few marks from some small stones left in the clay, they have a blue colour, so figure it's a bit of basalt. This leads me to trying a similar colour as  a brush work to the outside. I will try dulling a cobalt carbonate with some iron oxide. The right mix though? maybe 40/50 Cobalt/iron oxide. Your suggestion?

1 comment:

hodgsonstudio said...

Hi Andrew,
Here's a formula that we've used for cobalt slip:
30 grams Cobalt Oxide
70 grams Albany Slip (or Alberta Slip)

The iron bearing slip moderates the intensity of the Cobalt Oxide nicely; Using cobalt carbonate, there would be less of the cobalt component, but this proportion might be a good starting point.