PROPERTIES OF WOLLASTONITE AND DIOPSIDE WITH ADMIXTURES OF TiO 2/ ZrO 2 , AND SiO 2 *

A bstract Diopside and wollastonite from natural sources were mixed with TiO 2 , ZrO 2 , and SiO 2 . The firing and fired properties were studied. Certain admixtures were found to improve the color of the fired materials and at the same time produced exceptionally hard bodies of high density. Summary All of the mixtures of wollastonite or diopside with TiO 2 , ZrO 2 , and SiO 2 showed the short firing range typical of the alkaline earth silicates. Exceptionally high hardness and density were obtained with many of the compositions. The color of wollastonite showed the greatest improvement with 15% of TiO 2 and that of diopside with 10 to 25% of ZrO 2 .