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isolating leachable elements

updated sun 30 apr 00

 

iandol on sat 29 apr 00

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Joyce A. asks

----------------------------Original message----------------------------

I have another question:

If a slip, under a glaze, contains more than the limit, does the same apply?

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I think the technique of applying colourant materials in a slip, which will
vitrify with or within the clay, then isolating that layer under a hard, =
clear,
bright, craze free, insoluble glaze is one which will solve a lot of =
problems
for domestic pottery designers. There are many simple glazes in all the
temperature ranges which fulfil the criteria for inert surfaces.

In fact, it is the technique I use to decorate most of my pots.

Another point to consider. Is it necessary to use more than permissible =
limits
if less gives the desired degree of colour saturation. Why waste expensive
oxides or stains with onglaze or inglaze techniques when underglaze has the
potential to be so much more durable

Ivor.