The Channel Tunnel collection held at Brunel consists mainly of books and of papers such as correspondence, maps, plans, meeting minutes, and photographs. There are also eclectic artefacts such as this piece of rock, in a Eurotunnel branded protective case.
The packaging reports: “This piece of Chalk Marl has been excavated from the Channel Tunnel by the service tunnel boring machine near the breakthrough point. The Chalk Marl is the lower part of the lower chalk stratum, which stretches from near Folkestone to the coast at Calais and in which the majority of the Channel Tunnel is being excavated. Its grey colour shows that it is a mixture of clay and chalk. The Channel Tunnel is being constructed in this layer because it is more waterproof and consistent with the chalk layers above it.” The information is repeated in French, and so the packets of rock could be used as souvenirs at both ends of the tunnel.
The Chalk Marl is around 100 million years old, and will have had its origin at a time when dinosaurs were still roaming the lands that would become Europe. For more about the geology of the tunnel, see this page. The machines used to create the tunnel had to be made specially, and were each designed to work with the geology of a particular section of tunnel. For more information see The Robbins Company’s page.