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 colours are stable to Cone 8 except Rose, which is stable to Cone 4. Colours shown were fired at Cone 7. The Choxil Kit comes with each of the 10 different colours.