| Abstract: | The metal and its slag inclusions from the USS Monitor are mineralogical and geological artefacts of a vessel that has catalysed and documented the technology of maritime construction and warfare since 1862. Petrological study of a wrought iron disc from the hull of the Monitor reveals low‐carbon, high‐phosphorus ferrite with 4.8 vol% silicate slag, which includes phosphoran olivine, glass, wüstite and a silica polymorph. The sample, although made at the height of wrought iron manufacture, is of only mediocre quality and has a mineralogy, petrology and metallography that reflect the latter stages of puddling, rolling, annealing and 140 years of corrosion. |
