Seleziona una pagina

Fence of Ordovician slate from the Penrhyn quarries. The light-coloured spots, up to five cm by two cm on the cleavage, and <1cm thick, were spherical spots in mud before the rocks deformed during the Caledonian collision.
PhotoID318

Fence of Ordovician slate from the Penrhyn quarries. The light-coloured spots, up to five cm by two cm on the cleavage, and <1cm thick, were spherical spots in mud before the rocks deformed during the Caledonian collision.
PhotoID318

Photograph: Jim Talbot