鈣質砂摻和料和鹽的使用對陶器燒製的影響

The Behaviour of Calcareous Temper and Salt on Pottery Firing

由於鈣質砂在高溫分解的特質，這種摻和料的使用及發展，一直是考古學家感興趣的議題之一。此研究主要希望了解鈣質砂作為摻和料在不同燒製溫度下的變化，以及加入鹽水後所產生的不同。實驗發現，當超過800℃的燒製溫度範圍後，由於碳酸鈣分解成石灰及二氧化碳的作用，產生的石灰遇水生成氫氧化鈣時，劇烈的體積膨脹會造成試片的毀壞，無論鈣質砂摻和數量多寡，都會造成一定程度的損毀，使得高溫的試片在燒製上較為困難，然而鹽的使用卻能有效抑制鈣質摻和料分解的效應。

Due to the decomposition of calcareous sand at higher temperatures, the use and development of this kind of temper has long been an interesting issue in the study of pottery production. This study looks at the reaction between calcareous temper and pottery paste at different temperatures, and the associated influence of salt in the firing process. It is found that the decomposition of calcite occurs when the firing temperature exceeds 800℃. The subsequent products, calcium hydroxide and carbon dioxide, lead to expansion and bloating in the paste, and therefore the breaking of the pottery vessel. Thus adding calcareous temper makes it difficult to fire pottery at higher temperatures. However, such a situation can be controlled by adding appropriate amounts of salt to the clay paste.