Lastly , the potter would re-open the ventilation to re-oxygenate the kiln .
Lastly , the potter allow the temperature to drop , thus causing the non-decorated regions to revert to their natural red color .
Lastly , the potter would re-open the ventilation to re-oxygenate the kiln and allow the temperature to drop , thus causing the non-decorated regions to revert to their natural red color .