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GLAZE

Miscellaneous

• Family: None
• Region: None
• Mined At: Unspecified
• Raw Mineral: Yes
• Generic: No

Notes

(Richard Willis)

It has been said in many ways by many ceramicists that the more sand, the better the glaze; and, the less sand, the better the clay. Sand is the most common way of finding silicon and the most generic way of looking at it. All clays and glazes use silicon, and most glaze compositions have it. Salt, ash, lead, boron, etc. “glazes” don't have to have it (most don't, some do) but they need it in the clay they are to meld to. Strong fluxes such as these can be applied directly to silicon-bearing clay surfaces as washes, powders, granules or whatever, where they will, at their respective fusion temperatures, react with the silicon toward a melt, and the surface, when cooled, with have a glassy, ergo glazed, finish. Boron (such as “boric acid”), used alone, can melt prior to fluxing the silicon present and form its own glassy film, but this is rarely desirable since its adhesion is more like glue than meld and its hardness is more like cellophane tape than glass. Another saying: the more a glaze looks like a glaze, the worse it is; and the less a glaze looks like a glaze, the better it is: which is to say that the more integral the glaze is to the clay underneath, the better. At one end, boron “film” glazes; at the other end, the feldspar “meld” glazes. When it is hard (or impossible) to see where the glaze ends and the clay begins, one has a “real” glaze.

Authors

• Richard Willis (Owner)

XML

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<material name="GLAZE" descrip="" generic="0" rawmineral="1" searchkey="" loi="0.00">
<notes>
<note>It has been said in many ways by many ceramicists that the more sand, the better the glaze; and, the less sand, the better the clay. Sand is the most common way of finding silicon and the most generic way of looking at it. All clays and glazes use silicon, and most glaze compositions have it. Salt, ash, lead, boron, etc. &amp;#147;glazes&amp;#148; don\'t have to have it (most don\'t, some do) but they need it in the clay they are to meld to. Strong fluxes such as these can be applied directly to silicon-bearing clay
surfaces as washes, powders, granules or whatever, where they will, at their respective fusion temperatures, react with the silicon toward a melt, and the surface, when cooled, with have a glassy, ergo glazed, finish. Boron (such as &amp;#147;boric acid&amp;#148;), used alone, can melt prior to fluxing the silicon present and form its own glassy film, but this is rarely desirable since its adhesion is more like glue than meld and its hardness is more like cellophane tape than glass. Another saying: the more a glaze
looks like a glaze, the worse it is; and the less a glaze looks like a glaze, the better it is: which is to say that the more integral the glaze is to the clay underneath, the better. At one end, boron &amp;#147;film&amp;#148; glazes; at the other end, the feldspar &amp;#147;meld&amp;#148; glazes. When it is hard (or impossible) to see where the glaze ends and the clay begins, one has a &amp;#147;real&amp;#148; glaze.&lt;BR&gt;

</note>
</notes>
</material>

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