Metallurgical specimens collected for a metallurgical museum at Yale are valuable sources of information about early metallurgical practices in North America. Microprobe analyses of the inclusions in wrought iron samples are being made to see if the slag composition can be used to help determine the method of manufacture or to find the provenance of the iron. The analyses are intended to make a comparison of the observed specimen characteristics with available historical information on their manufacture so that an annotated catalog of the museum collection can be prepared. -- AATA