The Desborough Mirror
The mirror's decorated reverse side
Material	Bronze
Size	Height: 35 cm (14 in) Width (max): 25.8 cm (10.2 in)
Created	c. 50 BC–AD 50
Discovered	1908 Desborough, Northamptonshire, England 52°26′23″N 0°49′02″W / 52.4398°N 0.8172°W / 52.4398; -0.8172
Discovered by	Workmen while excavating for ironstone
Present location	British Museum, London
Identification	1924,0109

The Desborough Mirror is an intricately decorated English bronze mirror dated to c. 50 BC – 50 AD. It consists of a cast handle and a circular mirror plate which is highly polished on its front side to achieve reflectivity. The plate's reverse is decorated with intricate engraved and chased curvilinear patterns in the La Tène style, and filled in with basket hatching.

The mirror was discovered in the summer of 1908 by workmen outside Desborough, Northamptonshire, England, alongside a small and near contemporary brooch (also in bronze). Along with the mirror found in Birdlip, Gloucester, the Desborough Mirror is widely considered to be the finest of the roughly 26 surviving, fully intact and decorated Iron Age bronze mirrors, the large majority of which are English.^[1] It was acquired by the British Museum in 1924, where it is displayed in room 50 (Britain and Europe 800 BC–AD 43).^[2]

The Desborough was discovered in the summer of 1908 by workers excavating ironstone from a site at the east end of Desborough, Northamptonshire, England.^[3] It was found in the same field as a near contemporary 2 in (51 mm) bronze brooch, although the artefacts may not be from the same deposit (burial).^[4]

Decorated bronze mirrors of this type are specific to England; only a few continental examples are known. The majority have been found at graves dated to between 100 BC and 100 AD, indicating that in contrast to many other Iron Age artefact types, they were not hidden, discarded or just lost.^[5] Archaeologists and art historians generally agree that the Desbouough Mirror dates from c. 50 BC–AD 50, based on the assumption that its quality of design and execution indicates that it was created during the "peak" of Iron Age mirror design.^[6]

The Desborough mirror, like that found at Bridlip, is in relatively good condition to other extant decorated examples, a number of which may be reproductions given the disparity between their high-quality design and relatively poor-quality execution. There is light corrosion on around a quarter of the plates' surface area and on portions of the tubular loop.^[7][8]

The mirror's cast handle consists of a looped chain design, and is relatively simply designed compared to other extant comtemporary examples.^[8][9]

The mirror plate is roughly circular and lined with a continuous tubular binding strip.^[2] The front side and handle contain green patination, while the reflection on the front side was realised through extensive polishing of the bronze surface. Previous to this method, reflection was only experienced by looking into clear water.^[6] Thus historians assume the mirrors were commissioned for high-status women.^[10][2]

The reverse side is decorated with intricate curvilinear Celtic designs in the "Insular La Tène" style, including engraved spirals, crescent shapes and "trumpet" (three-sided) patterns.^[2][11] In total, 224 individual patterns have been identified.^[12]

According to the archaeologist P.R. Lowery, the decoration of Celtic mirrors was a "delicate, intricate [process] and demanded considerable precisely directed force".^[13] Because designing such complex and minutely intricate patterns requires a different skill-set to engraving, the mirror's production was likely overseen by a master craftsman who oversaw the work of a series of workshop members; during the design phase, when the outlines were lightly inscribed onto the plate and during the final application. This application of very small patterns required significant technical precision, and thus the final hatchings were most likely applied before the handle and tubing were attached, while the plate was held in a type of grip or vice.^[13]

The plate's broad outline appears to be that of a lyre (a stringed musical instrument similar to a lute) with flanking coils and was probably initially laid out using a scriber and compasses.^[10][2] The designs are symmetrically positioned, with those on one half reflecting opposite patterns on the other, but with the opposite shapes either "filled in" with darker shades (negative space) or empty with white space (positive space). Modern art historians generally agree that this inversion of positive and negative space was intended to sophistically invoke the way mirrors reverse the direction of any image at an equal and opposite angle.^[10]

A scriber and compasses would have been used to outline the 224 individual patterns^[12] before they were engraved by separate craftsmen.^[10]

• Catalogue entry at the British Museum