This plaque was probably made by Giacomo Raffaelli, an expert micromosaicist, who is often credited with developing the technique. The naturalism of the bird is achieved through the use of tiny tesserae, no larger than a pin head. The solitary bird on a branch was one of the first motifs Raffaelli used in his micromosaics.

The term 'micromosaic' is used to describe mosaics made of the smallest glass pieces. Some micromosaics contain more than 5000 pieces per square inch. The earliest attempts at micromosaic revealed visible joins between the pieces (known as tesserae) and a lack of perspective. Later artists such as Antonio Aguatti made huge advances in micromosaic technique, resulting in renderings that were truer to life. Glass micromosaic technique developed in the 18th century, in the Vatican Mosaic Workshop in Rome, where they still undertake restoration work today.

Sir Arthur Gilbert and his wife Rosalinde formed one of the world's great decorative art collections, including silver, mosaics, enamelled portrait miniatures and gold boxes. Arthur Gilbert donated his extraordinary collection to Britain in 1996.