Corpus figure

Incomplete Corpus figure (Corpus Christi) carved from jet. Medieval jet work seems to have been largely confined to devotional objects; particularly rosary beads. Corpus figures of this date in jet are extremely rare. Jet is a lustrous mineraloid, essentially a type of lignite (a soft brown sedimentary rock, created under extreme pressure). It is either brown or black, often with pyrite inclusions and is found in two forms: hard or soft, with a Mohs hardness between 4 and 2.5. Although it is easy to carve it is also brittle so requires quite a level of skill to work it effectively. There are several deposits of jet in England, most famously in the Whitby Mudstone Formation but also in the Kimmeridge shale seams in Dorset. Other sources are France, Spain and Poland, all of which could have been suppliers in the early Medieval period.