A great shining white sugar cube of a lump of quartz with an entirely square footprint! Christ, if it wasn't disrespectful to the lichen which had made there home upon it, I would be tempted to scrub it back to its Persilwhiteness to see it glow, glow, glow. An iceberg in a field.
It reminded me of the solitary and proud beauty of the Hawkstone in Oxfordshire. Gorgeous.