Quartz, stressed.

Quartz, stressed.

These specimens of quartz,  SiO2  were collected on the top of one of the highest hills in my locality. The hill is between Llandinam and Newchapel and is the site of a wind farm. The specimens were in a pile of material excavated to accommodate the concrete base for a turbine. The quartz is unusual for it's form, with the appearance of having been twisted by being subjected to pressure . The hill is 590 m 0r 1935 ft ASL, and is Silurian, Landovery,  in age.