The Ordovician slate of Blaenau Ffestiniog. A secret for 400 million years, laid down in smooth, silent reefs between Moelwynion and Manod.
Then, in a gnat's hair span of geological time mountains were turned inside out.
Miners hewed subterranean empires cathedrals of emptiness seeing only a candle's span of their dangerous work. Warfare would have been safer but less heroic.
The rock the masters didn't want was thrown aside, useless. Such a lot of it ten tons to every saleable one. So the mountains wore petticoats that shined like silver when it rained.
Great blocks were landed outside like innocent, dead whales no erratics, these, shot lines betrayed their deep origins. A reverse image of the mountain they were stolen from each has the ghost-memory of three pairs of hands that prised, strained and crewled on the passage to tip. Small, rejected slates from the mill were smashed like china on the banks.
The tips are restless with the subtle movements of a shoal of stranded fossil creatures. Generations spent nights listening to the slate shift on the tips, their orisons described by the dreamed shadows of shifting waste
Now the moment passes, a cloud shadow rumbles over as weather waits for the next move.
Time enamels the slabs with bright green lichen Sheep continue the work of reduction and movement dropping spoor following paths over older traces older signatures, fern, grass or trilobite.
Bright stonecrops find purchase now and calluna climbs on board in another blink of the epoch eye the slate will be secret again.
All images are copyright Iain Robinson 2017 and must not be used without prior permission. The depiction of a mine or site does not indicate that access is possible- permission should be sought before entering any private land. Underground exploration should not be undertaken unless properly equipped and with at least one experienced member of the party.