Invastigation of usage opportunities of copper slag in aventurine glazes

Ceramic pigments are kinds of high-cost products which are generally used in glazing, decoration, and design of artistic ceramic artworks and are produced through expensive technological processes. Although these products are commonly used in small portions in the formulation of bodies or glazes, their high prices increase the final costs of the produced ceramic artworks. Due to this fact, studies on the use of industrial wastes (such as metallurgical slags, red mud, and silicate-rich dust and ashes) as an alternative for commercial pigments have increased in recent years. Most of these wastes contain high levels of SiO2, Al2O3, Fe2O3, CaO, MgO, PbO, TiO2, K2O, Na2O, CuO, and ZnO and seem to be possible for use in ceramic glazes or bodies. In this study, the usability of copper slag is investigated as part of formulation in the production of artistic aventurine glazes. The used slag is obtained from Eti Küre Copper Mine near Kastamonu. At first, the chemical analysis of slag is determined via XRF. Then it is used in the ranges of 10 to 90 wt.% in double and triple glaze recipes with different raw materials. After firing, the aventurine surface formations of different glaze compositions and the effects of slag addition are investigated to develop a single-fired glaze suitable for artistic ceramics. The overall results show that aventurine glazes can be formed by using waste copper slag. It is finally concluded that waste copper slag can be used as a part of raw material instead of iron oxide in artistic aventurine glaze production.