Rather pleased with myself for recognising the feldspar crystal - OK it's a common rock forming mineral but I'm no mineralogist. Familiar from the Shap Granite of NW England, as used in pillars of the fabulous St Pancras Station in London. (The Victorian building uses stone from many geological formations along the rail line to Glasgow.)
Enlightening, on all fronts, Richard!
Rather pleased with myself for recognising the feldspar crystal - OK it's a common rock forming mineral but I'm no mineralogist. Familiar from the Shap Granite of NW England, as used in pillars of the fabulous St Pancras Station in London. (The Victorian building uses stone from many geological formations along the rail line to Glasgow.)