Nepheline Syenite A200 (200 mesh)Nepheline Syenite is a powerful flux used in many clay bodies and glaze recipes. While it is similar to feldspar in chemistries, Nepheline Syenite contains no quartz. This material is so loved because of its white color it adds to clay bodies and for its use in low temperature clay bodies to increase their thermal expansion. Information gathered from Digitalfire Ceramic Materials Database.