Blackford Hill and Dreghorn, Edinburgh - an excursion ...
Quarry: Andesite Lavas. Above the path up from the pond is an overgrown quarry cut out of the western face of Blackford Hill. The lowest rock seen is a pale trachytic lava overlain by a thin agglomerate containing trachyte blocks. Above this the main quarry face was cut into the single flow of dark fine-grained basic andesite which forms most ...