The two cobras flanking the agate and that on the loop show clearly the influence of ancient Egyptian jewellery. Amuletic devices form the principal decoration in Egyptian jewellery, where each has a magical or religious significance. The scarab beetle, usually carved in stone, refers to the sun and creation, while the cobra, often shown in a rearing attack position, symbolizes the protection of kings. Excavations in Egypt in the 1860s and the building of the Suez Canal (1854-69) first brought the treasures of the ancient civilization to European public attention. In 1862, the Prince of Wales (later Edward VII of England), visited Egypt. At Thebes, he was presented with jewellery set with scarabs, which he had copied by the London jeweller Robert Phillips for Princess Alexandra of Denmark, whom he married in 1863.
Phillips Brothers were well known for their revivalist jewellery, and were frequently patronized by the Prince and Princess. Princess Alexandra's 'Thebes' brooch gave her great pleasure, and was the only ornament which the Princess permitted to be shown on a marble portrait bust by Mary Thornycroft in 1863. The Princess allowed Phillips to make further copies of the 'Thebes' brooch between about 1863 and 1870, of which the Museum's version is one example.