All colors in the Sahara series are LEAD FREE. CL glazes restricted from use K-6 (ASTM D-4236/LHAMA) Cone 5-6. AMACO® Sahara High Fire Glazes are compounded to match porcelain and stoneware bodies. Matt and textured glazes suitable for stoneware and transparent gloss glazes for translucent porcelain are included in this series. Sahara High Fire Glazes work well and produce interesting effects when fired in reduction as well as in oxidation (reduction firing not recommended for HF-26). In liquid form, AMACO® Sahara High Fire glazes are ready-to-use while dry powdered glazes are mixed with water. Although these glazes may be applied on bone dry greenware for single firing, it is easier to apply them on bisque. HF-26 and HF-32 should be applied thicker than other glazes in this series. HF-36 should be fired to Cone 4 (2161°F, 1183°C) to obtain texture. For best results: if brushed they will need three coats, then clay and glaze may be matured at the same time, at the recommended firing temperature of Cone 5 (2205°F, 1207°C). A zinc-free, clear, transparent high fire glaze (HF-9) is also available. Because the presence of zinc in a glaze formula may change the appearance of certain colors (green, black, gray, etc.), a zinc-free clear is very important for application over underglaze decoration. Any variation in color intensity of the underglazes will then depend on the individual color stability at Cone 5. Firing range is from Cone 4 (2161°F, 1183°C) to Cone 6 (2269°F, 1243°C).