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fw: re: sub for lepidolite

updated fri 1 jun 01

 

Ababi on thu 31 may 01


Through Insight:
Lepidolite:


LEPIDOLITE.......... 100.00 100.00%
========
100.00

Li2O 0.55* 4.26%
K2O 0.39* 9.56%
Na2O 0.06* 1.05%
Al2O3 1.00 26.55%
SiO2 3.72 58.49%
Fe2O3 0.00 0.08%

Si:Al 3.74
SiB:Al 3.74
Expan 7.59

==================================
Now the substitute
=================
SPODUMENE........... 215.38 48.99%
CRYOLITE............ 91.37 20.78%
EPK KAOLIN.......... 86.00 19.56%
QUARTZ.............. 46.86 10.66%
========
439.60

CaO 0.00* 0.07%
Li2O 0.55* 4.36%
MgO 0.00* 0.02%
K2O 0.01* 0.15%
Na2O 0.44* 7.37%
TiO2 0.00 0.09%
Al2O3 1.00 27.52%
P2O5 0.00 0.05%
SiO2 3.72 60.14%
Fe2O3 0.01 0.22%

Cost/kg 0.43
Si:Al 3.71
SiB:Al 3.71
Expan 7.09
Using Cryolite means more Na2O less K2O.
The only other way is to use soluble materials. For crater glazes you need
low expansion anyway, so why bother!
Ababi

----- Original Message -----
From: "Hank Murrow"
To:
Sent: Thursday, May 31, 2001 8:08 AM
Subject: Re: Sub for Lepidolite


> >I was just wondering if anyone knows any substitutes for lepidolite. I
> >need if for a Crater glaze. So I need the gases it produces. Or if
anyone
> >has any glaze recipes for crater glazes.
> >thanks
> >nick
>
> Dear Nick;
>
> Try using spodumene and a small addition of Cryolite.
>
> Hank
>
>
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