Amazing Artefacts: A Well Travelled Stone

Andrew Lane

Hidden away in on the lowest shelf of a display cabinet in the Guildhall Art Gallery is a small, apparently undistinguished piece of stone. Found by archaeologists during the excavation of London’s Roman Amphitheatre,this Roman artefact nevertheless has a surprising story to tell.

Now fragmentary, the stone measures approximately 7 cm square,with a depth of around of around 2cm and is worked smooth on both the upper and lower surfaces. But it’s the colour that distinguishes the importance of this stone. The dark red to purple colouring is speckled with tiny inclusions of white that identifies this as imperial, or red porphyry, one of the most sought-after stones in the Roman world.

Small rectangular smooth stone with a dark purple colour, speckled with darker shades of red purple and white.
Fragment of Red Porphyry probably from a pavement (similar to the piece found in the excavations of London’s Roman Amphitheatre) ©Andrew Lane

Used principally for columns, statues and to veneer floors and walls – this piece probably originally formed part of a marble pavement. The Romans love of mosaic floors is well-known, but for the uber rich there was nothing better than a pavement formed of carefully cut pieces of beautifully coloured stone to flaunt your wealth. This piece may have been originated in the amphitheatre, perhaps in one of the boxes, or another prestigious building in Londinium.  

A large section of mosaic floor with green yellow and red square patterns.
Opus sectile pavement from the Curia (council) building in Rome ©Andrew Lane

But why was this stone so sought after? Firstly, it was the colour, purple was the colour of Roman authority. Nero once introduced an edict stating that only members of the imperial family could wear this colour - so it carried a certain cachet. Secondly, it was availability. This stone was only quarried in comparatively small quantities – and this made it a reassuringly expensive. Only one source of imperial porphyry was known in the Roman world, and this in the remote mountainous deserts of Eastern Egypt.

A wide view of a rocky desert landscape.
General view of the quarries of red porphyry, Eastern desert, Egypt ©Andrew Lane.

 So nearly 2000 years this incredible artefact undertook an amazing journey. Quarried from the top of an Egyptian mountain, it was then transported 100 miles across the desert to the Nile and the over a thousand miles to the Mediterranean Sea. From there it began a perilous journey by sea, possibly stopping in the port of Rome, Ostia, before continuing its journey to Britain. So, the idea of embellishing our homes and public buildings with expensive, imported stones is nothing new – just ask the Romans.

A map illustration showing most of Europe, highlighting Rome in Italy
A map of the Roman World with the site of Mons Porphyrites marked.

 If you would like to find out more you can watch this 5-minute talk.