Welcome to Bloomsbury
Standing outside a building in Bloomsbury, Beneath the Skin by Peter Randall-Page may look like a modern artwork, but it’s also a geological time capsule. This sculpture, carved from dark Kilkenny limestone, contains evidence of life and environments that existed more than 300 million years ago. Through this EarthCache, you’ll explore how geology and art combine, showing how sedimentation, fossilization, compaction, and human craftsmanship reveal what truly lies beneath the skin of the Earth.
The Story of Kilkenny Limestone
The stone used for Beneath the Skin began forming about 330 million years ago during the Carboniferous Period, when much of what is now Ireland lay near the equator beneath a warm, shallow tropical sea. Over time, the shells and skeletons of countless marine organisms such as corals, brachiopods, crinoids, and microscopic plankton settled on the seafloor. Layers of this calcium carbonate-rich sediment slowly built up and compacted under pressure, forming limestone.
As the layers thickened, chemical changes cemented the grains together into solid rock. In some regions, tectonic pressure folded and fractured the beds, creating the dense, fine-grained Kilkenny limestone found in southeastern Ireland. Its dark color comes from carbon and organic matter mixed into the sediment before it hardened. These small inclusions give the rock its characteristic grey-to-black hue.
The limestone used here was quarried near Kilkenny, transported to London, and hand-carved by the artist in 1991. Although it has been transformed by human tools, the stone still records its original marine origin. Many pieces of Kilkenny limestone contain visible fossils, especially if polished or wet, providing a window into an ancient oceanic ecosystem.
What is Limestone?
Limestone is a sedimentary rock primarily made of calcium carbonate (CaCO₃), often derived from the remains of marine organisms. When compacted and cemented over long periods, these deposits form solid rock layers. Limestone can:
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Contain fossils that record marine life
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React with acid such as vinegar due to its calcite content
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Develop karst landscapes including caves, sinkholes, and cliffs when dissolved by water
Kilkenny limestone is especially prized for its fine grain, dark color, and ability to take a high polish, making it ideal for detailed sculpture and architecture.
Tasks for This EarthCache
To log this EarthCache, visit the site and complete the following tasks. Send me your answers via Geocaching or email.
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Include "Beneath the Skin - Bloomsbury - GCBE99Z" on the first line of your message.
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Look closely at the surface of the sculpture. What color variations do you notice? Describe the grain size and texture. Is it smooth, rough, uniform, or varied?
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Can you spot any small shell-like patterns or fossil fragments? If so, describe what you see and where on the sculpture they appear. What does the presence or absence of fossils tell you about the environment where this limestone originally formed?
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Touch the stone gently. Does it feel soft or hard? Based on its polish and condition, do you think this type of limestone weathers quickly or slowly in the London climate?
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In your log, attach a photo of yourself or a personal item with the sculpture. (Note: photos predating the publication of this EarthCache are not accepted.)
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