My work this semester is based on questioning the relationship between object and plinth; a removal of the object from its context through the promise of visibility and an anticipation of temporality to the relationship. I wanted to also explore the glazes’ dimensionality beyond being seen as a surface material, as having substance and can become valuable in indicating the object-plinth relationship that is now made permanent through the materiality of clay, where both parts are extensions of each other.
Crystalline glaze recipes contain zinc oxide, silica, and fluxes.
crystals of zinc silicate (Zn2SiO4) are formed.
A window of approx. 72 C (130 F) exists in which to grow crystals.
Crystalline glaze is fired higher than the melting temp. of the glaze, at least 222 C (400 F) hotter. Once this point is reached, the temp. should be quickly reduced to the temp. range for crystal formation, then kept within this range for a predetermined time.
Sequence to promoting crystal formation:
- Getting to max. temp. as quickly as possible.
- Rapidly cooling to the crystal growing range.
- Extendeds oaking, or slowly dropping and raising the temp. within the crystal growing range during the crystal growth period.
- Shutting the kiln off and cooling naturally.