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A combination of cobalt and titanium produces matt greens with the right amount of alumina in the glaze. For high-firing, this green can be obtained by putting cobalt and titanium (often as rutile) into a shino-type high feldspar (or nepheline syenite) glaze. To get it to mature at mid-fire we can add frit to the set of fluxes and additives, and construct a grid to find where it occurs at the lower temperature. To go from stoneware (e.g. ^ 9 or 10) down to mid-fire (e.g. ^ 5 or 6) firstly enter the original flux and additive set (names and amounts) into the Calculation Page. Now add frit to the flux set and by trial and error, recalculating each time, find what number you need to enter in Row 2 to give 30% frit in the corner C glaze (glaze 31) on the resulting recipe sheet ("35 Recipes for the Set"). You then produce a grid from the corner glazes provided where it says: "Corner Glaze Calculation - Batch Recipes for Volumetric Blending". Once the set is fired it will show where the green occurs with the new set of fluxes. Different frits will give different results; the frit lowers the maturing point for all the glazes in the set by brute force.

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