A jack of plate shown with its x-ray and an x-ray detail of one of its iron plates

The jack of plates: Evidence of re-cycling

The question

A common type of armour during the 16th-century was known as the jack of plates. These were made up of a large number of pierced iron plates sewn into a textile garment to cover the upper body.

Because of the deterioration of the textile parts, surviving armours are exceedingly rare and very fragile. Could X-radiography tell us more about the metal plates hidden beneath the surface?

Results of analysis

The great variety of plates within each garment suggests that jacks were often damaged and reconstructed. The example shown is one of several that also provided evidence that the plates had been recycled from an earlier type of armour known as a brigandine, distinguished by a cluster of rivet holes and occasional obliquely cut platelets.


Examination of six similar garments within the Royal Armouries provided a much better understanding of this type of armour and allowed comparison with archaeological finds, such as a recently recovered jack of plates from Chester.


An outcome of this work was the publication of Finds Research Group Datasheet 36 that covers Jacks and Brigandines. This was targeted at practicing archaeologists with the aim of improving the chances of recognition of individual plates that might otherwise be mistakenly misclassified as washers or fragments iron strapping.

Did you know?

Six Eiffel Towers

During the siege of Sebastopol the British and French armies fired 10,000 tonnes of iron shot, 510,000 round shot, 236,000 howitzer shells and 350,000 mortar shells. That’s a total of about 43,000 tonnes of iron: the equivalent of six Eiffel Towers!