The
appearance of devitrification varies from mild
streaks as a dirty appearance on the surface, to at worst a granular
surface that breaks away in small pieces. The glass will often have
raised sharp corners in cases of severe devitrification.
Avoiding
devitrification relates to cleaning, firing
rapidly through the devitrification range, avoiding
devitrification-prone glasses, and grinding edges as little as possible.
Repairing
devitrification requires the removal of the devitrified surface.
This can be done by sandblasting, sanding the surface by hand, using
acid pastes to remove the surface. Then the piece needs to be fired
again to a fire polish.
To
ensure a polished surface a devitrification solution may need to be
applied. It can be a commercial product or a borax solution. Any
devitrification solution should be applied evenly.
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