Choxils are a solid underglaze drawing medium like a chalk with the density of a pencil. Choxils are the diameter of a pencil and can be sharpened in most pencil sharpeners. Choxils are applied to bisque ware. All colors are stable to Cone 8 except Rose, which is stable to Cone 4. Colors shown were fired at Cone 7. Our Choxil Kit comes with each of the 10 different colors. Our Choxils are AP (Non-Toxic)