search  current discussion  categories  glazes - crystalline 

: crystals in my glaze bucket?

updated sun 9 feb 03


iandol on fri 7 feb 03

Dear Saundra,

An interesting question you ask

<surface of the glaze, beneath a couple of inches of clear water. The =
glaze had been undisturbed for about two months. ...The largest hexagon =
was about 1/2" thick.>>

Difficult to say but I think this has something to do with the Nepheline =
Syenite and the Gerstly Borate. both have a limited degree of solubility =
in water, it being known that Sodium Ions can be leached out of the =
rock. Once in solution it is possible that one of the Sodium Borate =
salts has started to crystallise out of the aqueous solution as a =
hydrated salt, that is, one which has water of crystallisation. Or it =
might be the hydrated form of a double salt incorporating sodium and =

What is certain is that removal will change the qualities of the glaze.

Best regards,

Ivor Lewis.=20