Biscuit, refers to pottery that has been fired but not yet glazed. Biscuit is any pottery after the first firing and before any glaze is applied. This can be a final product such as bisque porcelain, or unglazed earthenware, often called terracotta, or, most commonly, an intermediary stage in a glazed final product. The first firing is called the biscuit firing, and the second the glaze or glost firing.