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mystery - disappearing blue veins in clay

updated thu 19 may 05

 

Carole Fox on wed 18 may 05


I probably wouldn't have believed this if I hadn't seen it with my own
eyes. I had some clay trimmings that I wanted to reclaim. I put them in a
clean white plastic bucket, added slurry water from throwing the same clay
body (Laguna S3031 woodfire Bmix, which is creamy white in color). When
the mixture was about as thick as pudding, I put it in a white canvas bag
and hung outside to firm up. After 2 days, the mix was still quite soft as
expected, but with severe thunderstorms coming in, I moved the bag to the
garage, where it stayed for a week and a half. (OK, I just basically
forgot about it. You know what they say - "out of sight, out of mind".)
Anyway, when I finally remembered the clay, it was quite stiff and I had
some difficulty peeling the canvas away. When I did get the canvas off, I
noticed dark blue wavy vein lines a around the lower third of the clay mass.

When I cut through the clay with a wire, I saw that these veins of color
were throughout the lower portion of the body and not just on the surface.
They did not even remotely resemble any kind of mold - just colored clay.
I examined the canvas bag, and there were no blue marks, streaks, drips(or
any other color for that matter) on it whatsoever. It also had no blue
printing or dye on it anywhere. I whacked the clay on the floor a couple
of times to loosen it up, which worked quite nicely. I then wedged, sliced
and recombined the clay over and over again, thinking that I could work out
the blue. Well, the veins got thinner and thinner, and more evenly
distributed throughout the clay, but after a full fifteen minutes of
wedging, were still quite visible.

I decided to stop before my arms dropped off, put the clay in a plastic
bag, and left it. Four hours later, I came back to have another go at
wedging. Surprise! The blue had completely disappeared! The body was the
normal cream color. I threw a pot with it, and it felt completely normal.

So I am stumped by this "now you see it now you don't" color. Does anybody
have an idea what could have happened?

Carole Fox
Dayton, OH

Earl Brunner on wed 18 may 05


By your description, I'm almost sure is anaerobic mold or bacteria. The very process of wedging exposes it to air and it fades away. I do a lot of recycling for the city program and the organics often act this way, when exposed to air or oxygen, the black or what ever color goes away.

Carole Fox wrote: I probably wouldn't have believed this if I hadn't seen it with my own
eyes. I had some clay trimmings that I wanted to reclaim. I put them in a
clean white plastic bucket, added slurry water from throwing the same clay
body (Laguna S3031 woodfire Bmix, which is creamy white in color). When
the mixture was about as thick as pudding, I put it in a white canvas bag
and hung outside to firm up. After 2 days, the mix was still quite soft as
expected, but with severe thunderstorms coming in, I moved the bag to the
garage, where it stayed for a week and a half. (OK, I just basically
forgot about it. You know what they say - "out of sight, out of mind".)
Anyway, when I finally remembered the clay, it was quite stiff and I had
some difficulty peeling the canvas away. When I did get the canvas off, I
noticed dark blue wavy vein lines a around the lower third of the clay mass.

When I cut through the clay with a wire, I saw that these veins of color
were throughout the lower portion of the body and not just on the surface.
They did not even remotely resemble any kind of mold - just colored clay.
I examined the canvas bag, and there were no blue marks, streaks, drips(or
any other color for that matter) on it whatsoever. It also had no blue
printing or dye on it anywhere. I whacked the clay on the floor a couple
of times to loosen it up, which worked quite nicely. I then wedged, sliced
and recombined the clay over and over again, thinking that I could work out
the blue. Well, the veins got thinner and thinner, and more evenly
distributed throughout the clay, but after a full fifteen minutes of
wedging, were still quite visible.

I decided to stop before my arms dropped off, put the clay in a plastic
bag, and left it. Four hours later, I came back to have another go at
wedging. Surprise! The blue had completely disappeared! The body was the
normal cream color. I threw a pot with it, and it felt completely normal.

So I am stumped by this "now you see it now you don't" color. Does anybody
have an idea what could have happened?

Carole Fox
Dayton, OH

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Earl Brunner
e-mail: brunv53@yahoo.com