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can fired glaze change colour

updated fri 10 jun 05


Avril Farley on thu 9 jun 05


In my experience glazes containing strontium are affected by light, =
sometimes temporarily.

Avril in the Forest UK

JOYCE LEE on thu 9 jun 05

Avril Farley responded to:
" Can fired glaze change colour"

No Guru here...... but yes, definitely. I
experiment with this all the time simply by
placing pots out in my desert yard..... often
for years. Most haven't changed noticeably,
but some have rather remarkably.

I have what was a shino (Mel's, I think) on
the bottom and a rutile wash over the top.
Looked just like all my other pots wearing the
same glaze. Several years in the sun have
changed the shino to orange.... a popsicly kind
of orange with no drab white which it had
exited the kiln wearing. The rutile wash now
is a silvery/gold.

Another huge fat pitcher is Mel's shino on
dark brown clay. I'd forgotten that I'd never
wound up with a shino-look using shino on
brown clay. Years in the sun is changing the
area around the lip to a somewhat typical
off-white with specks.... same with the area
just above the bottom of the pitcher. This
was a slow process taking maybe 5 years....
two miles from Inyokern, which in one Farmers
Almanac was listed as having the most days
of sun in the U.S.... not the hottest..... but the
greatest number of sunny days. However,
even though the process was slow, I did not
observe its progress. I look at the pitcher
every time I get out of the car..... suddenly
one day a few weeks ago I saw the white/gray
shino..... and the area of white is expanding
still..... now rather obviously.

What does this mean? No idea. But ever
interesting to me. (Does this result from the
world's lengthiest Hank Murrow cooling......
or firing down....... process?)

In the Mojave starting the one or two-cup
teapots ..... 85 surviving minis is enough.