In Valchiusella, near Traversella on the left side of the Chiusella river, some rivets in steels were found and they can be dated at the end of the 18th century and the beginning of the 19th one. The chemical analysis has pointed out that the steel is very poor in carbon, but in the essentially ferritic structure, some significant pearlitic zones have been observed by metallography in the core of the product, as it could be expected if a forging carburizing treatment was applied. Some fragments of entrapped slags have been detected within the analyzed steel products and have been chemically analyzed by EDS as well as the slags found in the rivet and the non-metallic inclusions of the steel. The chemical composition of the non-metallic compounds has been investigated by the software ThermoCalc. The data obtained have been compared with the results of the metallographic analysis of the steel. The thermodynamic conditions for the production of the investigated steels have been underlined in order to improve the knowledge of the features of the reduction process used during that period.