Mayco cobblestone sg201black cobblestone Cobblestones create a textured "cobbled" surface when fired Certified AP on-Toxic and Food safe; however not recommended for food surfaces due to surface characteristics. Apply over another glaze and during the firing process, a shattered pattern of raised, irregular chips will emerge. Fire to Cone 06 (1828F, 998C). Made in USA. Jar is 4 oz The underlying glaze will appear in the cracks.