5KG SILICA SAND (50 MESH)

Quartz sand. A refractory used on kiln shelves to ease shrinkage movement of large pieces or, in limited amounts, as a fine grog in clay bodies.  
Coarse sand (~99% retained on 70 mesh) is also available as are powdered grades.

For more information on silica sand, see the Digitalfire.com Reference Library of ceramic materials.