Alpine Catchfly (Silene suecica) is only found at two sites in the UK (one in Angus and a very small colony in Cumbria). The plants at the Cumbrian site are very high up, unfortunately due to people taking the lower down flowers for their gardens. This is why my photograph is somewhat distant!
Plantlife informs that Alpine Catchfly tends to favour rocks with a high heavy metal content and has been used by prospective miners to indicate fresh ore deposits. Because of its unusual ability to grow in soils with heavy amounts of copper, Alpine Catchfly is used in geobotanical prospecting as a copper content indicator.