Collection of Samples

Several weeks ago I collected my final samples before returning from Barbados. After interviewing several potters it was discovered that two of five do not use local Barbados clay. When asked for a reason, one potter stated that there was too much variation within the local clay. This means that the content of iron and sand within the clay was not uniform throughout the entire clay deposit. Differences in the variation of the clay body can lead to variance in the firing temperatures of the pottery. If too much iron is present in the sample, the ceramic will fire at a lower temperature with the iron melted out of the clay. This would lead to more shrinkage in the ceramic than desired, and in turn to the breaking of the vessel due to the high heat of the kiln. Too much sand presents an entirely different problem, the ceramic fires at too high of a temperature. This leads to seeping of the ceramic, thus ruining any expensive mahogany tables underneath it. The potter explained that he had lost a whole kilns worth of work because of the local clay and changed sources, as well as complaints from clients about mahogany tables being ruined.

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