Chrome
"Chrome is a rather versatile and fickle colorant," (Chappell). Chrome oxide (Cr2O3) is commonly used for achieving greens. However, in the presence of zinc, chrome can produce brown. Glazes with tin oxide present will often blush to pink if fumed with chrome or if chrome is present in the glaze with the tin, often intense pinks occur. If fired above cone ^6, chrome will fume and become a gas in the kiln. Common saturation percentages for chrome at low saturation range from (.25 to .5%) and at higher percentages from (1 to 2%). Chrome is a refractory.
Read more about this topic: Ceramic Colorants