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rutile/titanium and expansion

updated fri 30 apr 99


Chris Schafale on thu 29 apr 99

This one is for us glaze-newbies. I was playing with the Floating
Blue recipe this morning on Insight (after realizing that this
much-loved and reviled glaze was crazing on some new pots). The
expansion on this glaze is really high (7.98), so it's no
wonder that it crazes. I had assumed that this was the result of all
that Neph Sy, which no doubt it is, largely. However, I happened to
notice that when I removed the 4% rutile, the expansion dropped from
7.98 to 7.69 (quite a big jump for 4% of anything). This is
significant because I've been in the habit of calculating and
evaluating my glazes without colorants (including rutile). So, just
for future reference, if you're concerned about expansion and
preventing crazing, be sure to include the rutile or titanium in your


Light One Candle Pottery
Fuquay-Varina, NC