Granophyre.

Granophyre.

This specimen of Ercall granophyre is as it's name suggests,  from Ercall quarry in the Shropshire hills. It's age is about 560 million years,  placing it in the Ediacaran period.  At the exposed nonconformity,  the pinkish coloured  porphyritic granophyre is overlain by the lower Cambrian wrekin quartzite.  The quarry is an SSI site, and no hammering is allowed,  so  the specimen was collected from loose pieces on the quarry floor. It is not an easy rock to identify, needing a microscope and thin section to observe the quartz and feldspar intergrowth. The pinkish colour is very striking, and the photograph is as true to colour as I can get.