Chemické složení loštických pohárů


The paper summarizes results of geochemical examination of the Loštice pottery. A clay nodule found during archaeological works was used for a part of tumbler replicas´ production as a plastic raw material. At the temperature over 1 200 °C, the replicas made of loess collapsed. The affect of garnets on formation of “blebs” was experimentally verified. The results showed that the ceramic tumblers of the (010) and (020) groups were made of clay soil with the addition of almandine garnet as non-plastics. The “blebs” form by thermal decomposition of almandine. The firing temperature must exceed 1 200 °C. Cordierite (sekaninaite, possibly ossumilite) crystallizes from the melt. Another part of replicas was made of local loess.

Klíčová slova:
pottery, technology, almandine melting, chemical composition, chemical formula, firing temperature

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