A compact UHF RFID tag is proposed to be integrated into small cavities carved out of metal objects. To identify each object during the entire fabrication and assembly line, the UHF RFID tag is applied just after the die casting operations needed to model the metal component. Hence, the tag has been designed to withstand the high temperature. Preliminary tests are here described to assess the tag performance when used under high temperature conditions, pointing out a read range of 30cm above 100°.