OXIDES AS CLAY COLORANTS

A challenging but wonderful learning experience for my Ceramics II students

is this Stacked Clay assignment.

I give the kids white Porcelain slip 

and they mix their own colors from the 4 oxides we have to choose from.

Then they poke holes into a piece of white Porcelain clay and pour their colored slips

into the clay body.

Wedging is next to mix everything together until the porcelain turns another color.

In this piece above,

 which I think I may have shared 2-3 years ago,

I mixed Cobalt Carbonate into the white clay body 

so that it would turn blue in the final glaze firing.

Then I rolled pieces of this blue clay into slabs 

and stacked alternated slabs of white between them.

I rolled all top & side edges together to bond the slabs into one

 and push out the air bubbles in between,

then rolled the bonded combo. slab into a long piece so that I could roll that up into a jelly roll.

Phew!

Next the roll was turned on it's side,

and thin slabs were cut and inlayed onto a waiting white porcelain slab.

The bowl was then formed over a newspaper mold and feet attached.

Above is another bowl/plate that I made for a demo. maybe 2 years ago.

It's a bit hard to see the actual second color I mixed from this pix,

but I made one mixture of Red Iron (brown),

 and another of Chrome Carbonate (pale greenish blue grey).

I really liked the elongated form that came from this demo.

I never plan anything ahead or know what I'm going to come up with,

so it's always a surprise.

Helps me to be more creative.

This was my demo. last year for 2nd year student senior Sarah Chang.

I lucked out and ended up with 3 pieces.

The first one is the glass form on backside left.

In that piece you can see the pattern I stacked the Blue and white slabs in.

But I ended up with so much leftover clay that I didn't want to throw away it,

so I overlapped the edges I had cut off and made another glass form,

the one on the right back.

Once again,

as I cut off edges, 

I had tiny pieces of slab left over,

so again I overlapped them and managed to use them all up in this last tiny vase form in front.

Way too much fun!