The morphology of reaction zones between platinum metal and silicon carbide ceramic at 973 and 1023 K is considered in detail. A periodic pattern of carbon bands embedded in Pt7Si3 is observed at both temperatures. The growth of platinum silicides at 973 and 1023 K is compared. Cross-sections of the Pt-Si-C phase diagram at those temperatures are presented. The periodic layered morphology is explained via a ’repeated splitting’ mechanism.