By studying remains from laboratories of the past, archaeologists are able to reconstruct various processes.  The following images are micrographs taken from crucibles that were used to process copper and bronze at Mapungubwe, one of southern Africa's first state systems.

Map 3-1: Photomicrograph of a sample of crucible slag showing glassy phases. Different oxides have colored the glass differently. It is possible that the crucible was used for local glass processing.

MAP 6- 5: XPL Photomicrograph of a sample of crucible used to process copper and bronze at Mapungubwe. The crucibles were made of clay with different minerals. By studying the mineralogy of the clay, archaeologists may identify sources of the raw materials used.

RSV9 – XPL Photomicrograph of a sample of crucible slag from Rhenosterkloof in the southern Waterberg. The micrograph shows various phases such as elongated crystals of tin oxide (grey).