During stern excavations well over 200 fragments of lead sheathing or patching were recovered. Since the corrosion products of lead are stable (Hamilton 1994:102), conservation treatments have been minimal. Selected lead fragments have been cleaned by electrolysis or placed in a ten percent solution of hydrochloric acid (HCl) to reveal surface details that occasionally were obscured by a thin layer of calcium carbonate, lead sulfide and/or lead oxide. Chemical cleaning or electrolytic cleaning is non-abrasive and, in this case, permitted surface impressions of what was very likely sail cloth to be revealed.
Several lead objects, notably the bodoques (lead-covered iron shot), were found with adhering concretion. These pieces were easily freed of concretion with an air scribe, polished with baking soda, and sprayed with a protective coating of acrylic spray.
Fig. 74. Documentation and study of artifacts, such as this analysis of lead sheathing, is a routine part of laboratory work.