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Week 5 â€œRaw glazesâ€ are those that are applied to the clay at the unfired, leather hared or dry stage. When making a glaze for __________ ______ clay, we have to increase the plastic, clay content of the glaze. However, a raw glaze for dry clay needs a decrease in ___________ content. Bone dry, silica Leather hard, water bisque ware, alumina Bone dry, water Most raw glazes will need around ___-____% of clay in the recipe. 10-20 20-30 30-40 40-50 A very interesting glaze can be had by adding iron oxide into a ______ _____ and ____________ _____________base glaze. This produces a bright orange-red colour response. bone ash, lithium carbonate dolomite, barium oxide boric oxide, magnesium carbonate whiting, zinc oxide For those only doing oxidising firing at stoneware temperatures, certain colors are readily found with the additions of cobalt (blues), iron (browns), copper (greens) and opacifiers such as tin, titanium, and zircon (white). Some colours, however, are much harder to achieve and true res and bright yellows are usually only possible with help from _______________ ______________ ___________. reduction firing only second and third firing luster glaze firing commercially prepared stains This weeks questions were taken from text in Glazes Cone 6, Michael Bailey, 5th Printing 2010. University of Pennsylvania Press best, Pres Answers: 2 )Leather hard, water. . Therefore, in making a raw glaze to go on leatherhard clay, we need to increase the plastic, clay content of the glaze--this will allow the glaze to shrink in step with the clay as it dries. Or, for glazing on dry clay, we need to cut down on the water content of the glaze. 3) 30-40%. . Most raw glazes will need around 30-40% of clay in the recipe. The result is that we can end up with a lot of alumina in the glaze, which is fine if you are after satin and matt glazes, but hopeless if you want them to be transparent or crystalline. The secret to solving this problem lies in realizing that not all clays are high in alumina! 1) bone ash, lithium carbonate. . This is a very interesting glaze where the addition of red iron oxide into a high bone ash and lithium carbonate base glaze, produces a bright orange-red colour response. (Unfortunately none of the other colouring oxides seem to react in this unusual and amazing way). This interesting glaze is called Orange-red iron glazes by Bailey.(pres) 4) commercially prepared stains. . Answer and question taken directly from the text on page 22, end of paragraph 1(pres)