Glaze formulation using selected geological material from Lake Nakuru and Kiambu Counties, Kenya

Abstract

The use of glazes and glaze formulation has evolved over time and glaze styles have been developed with characteristics of certain world regions, out of the use of locally available materials. A pilot study conducted in three studios within Nairobi to assess the use of local glazes/formulations revealed that the studios did not use local glazes or formulations and that there was need for research on local glazes and formulations. Based on the above, this study was concerned with using locally available geological material from Nakuru and Kiambu Counties to formulate glazes to be used on ceramic ware for ceramic artists in Kenya. The study set out to collect data of 52 geological materials for formulation; 29 from Nakuru County and 23 from Kiambu County. These materials underwent a wet milling grinding process using a porcelain ball mill at Kenya Industrial Research and Development Institute (KIRDI). After which, they went through a studio testing process of low and high firing tests with temperatures, of 10500C and 12000C on small slabs of Nyeri clay and thereafter an elimination of 13 samples for formulation. The 13 samples underwent a qualitative and qualitative certified chemical analysis test using an Atomic Absorption Spectrometer (Spectr AA- 10) at the Ministry of Mining. The test results were used in formulating 145 glaze recipes by introducing additives that generated glaze compositions which gave both functional and aesthetic qualities for application on ceramic ware. The results of the majority of the glaze formulations affirmed their use on ceramic ware. To confirm that the findings would be of benefit to practicing ceramic artists, two clay samples of ceramic studios within Nairobi; Jacaranda Workshop and Wakenii Creations were also tested and they received the glazes well. The geological materials studied were therefore found to be suitable for glaze formulation and could be put to use by local ceramic artists. Further research should be done into the improvement and generation of more colour range and textural effects of glaze formulations for mass production in ceramic manufacturing.