Conservation of heritage artifacts is a very sensitive task as conservators usually have very little in-formation about the artifacts. Moreover, due to the uniqueness and the historic value of these artifacts, invasive analysis are not always possible. Therefore, without sampling options, conservators are re-quired to use non-invasive diagnostic methods in order to identify the metal characteristics of the artifact. When confronted with an unknown artifact, conservators generate conceptual models of the cor-rosion forms. These models are based on formal representations of corrosion forms, but are not directly exploitable for drawing hypotheses regarding the underlying metal. This paper presents the design of a data structure generated from the conceptual models which supports the comparison and retrieval of corresponding artifacts. Integrated with a database of heritage artifacts, this data struc-ture offers advanced decision support to conservators confronted with unknown artifacts.