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: cone 10 transparent/clear glaze recipe needed

updated sat 23 feb 02


iandol on fri 22 feb 02

Dear James Bowen,=20

You say <firings turns iron bearing clays gray.>>=20

I have experienced this effect.

My understanding is that you will be reducing from a temperature below =
the incipient fusion point of your melting flux. This is what will =
change the colour of your Iron compounds in your clay. For Calcium to =
have an effect you would have to propose a chemistry. From memory, =
Barium Ferrites are red brown so I would imagine Calcium Ferrites would =
have a similar hue.

To get a bleaching effect the new chemical which forms must be either =
colourless or white, or it must be volatile and and sublime or =

There may however be alternative opinions.


Ivor Lewis