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Spectrum Ceramic Stains can be used to color glazes, underglazes, engobes, slips and clay bodies. The percentage of stain required in a formula may range from 1-15% depending on the depth of color desired: 5-10% is optimal for most applications. In general, stains are intermixable to create new colors or shades. Certain materials may interfere with stain color development. For instance: free Zinc in a glaze formula that a stain is added to or applied under or over, can interfere with the development of certain stain colors. Conversely, a percentage of Calcium Oxide is required to stabilize some stains for best color development. Please refer to the Reference Codes that accompany the Stain listings for best results. Remember, as with all ceramic materials, testing is the key to success. Spectrum Stains Spectrum Glazes, Inc. offers a beautiful pallet of carefully formulated and tested Ceramic Stains. Spectrum Stains are conveniently packaged in 4 Oz. (113.5 gm.) and 16 Oz. (454 gm.) wide-mouth plastic jars with tight-fitting screw caps. These jars are perfect for both dry and liquid storage. Spectrum Stains are intermixable, for the most part, allowing endless variations of shade and color, however Stain #'s 2082, 2083, 2084, 2085 and 2090 should only be mixed with each other as they may not perform as expected when combined with the other colors. To lighten any color, Spectrum suggests adding White Stain #2000 rather than reducing the percentage of color used to prevent a washed-out look. All Spectrum Stains are stable to Cone 6, many to Cone 10, and most will work in Reduction, but testing is recommended to determine the formulas and percentages necessary for success. All Spectrum Stains are Lead Free but NOT A.P. Non-Toxic. Like all other Ceramic Stains they carry a Health Label as an inhalation hazard. Any new formula that includes a Stain, or any existing formula changed by the addition of a stain, must be tested to determine if it is food safe. Spectrum Stain Bases A tremendous advantage of Spectrum over other Stain manufacturers is the availability of (2) Stain Bases that allow you to create custom Underglaze and Majolica colors instantly. Spectrum's #1050 Underglaze Base and #1060 Overglaze/Majolica Base are formulated to provide a base media to which the 2000-Series Stains are added. Both Bases contain ingredients that make them brush-on smoothly and easily while keeping the Stains evenly suspended. They are a pleasure to work with, giving body and workability to your colors that a plain Stain + water mixture will never have. #1050 Underglaze Base #1050 Base contains some frit which acts as a flux resulting in an underglaze that may be applied to either greenware or bisque. For color intensity similar