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lead chromate -> chromium oxide

updated sat 29 oct 05

 

Patrick Herring on sat 29 oct 05


Hello,

I'm wanting to try out a Lucie Rie pink glaze containing lead chromate
which you can't buy anymore (in the UK). So I have some green chromium
oxide, which I assume is Cr2O3. Also I'm new to mixing my own glazes. Is
this the right calculation to make:

molecular weight of PbCrO4 = 207.2 + 52 + 16x4 = 323.2 g/mol
molecular weight of Cr2O3 = 52x2 + 16x3 = 152 g/mol

so the replacement weight of Cr2O3, giving the same number of chromium
atoms, is 152/323.2 x 1/2 of whatever weight of PbCrO4 would have gone
in, which is about a quarter. So you could just multiply up the other
ingredients by 4.

Thanks.


--
Patrick Herring, Leeds, UK