Glaucophane Schist (1kg)

Glaucophane schist also known as Blueschist is a metavolcanic rock that forms by the metamorphism of basalt and rocks with similar composition at high pressures and low temperatures, approximately corresponding to a depth of 15 to 30 kilometers and 200 to ~500 degrees Celsius. The blue color of the rock comes from the presence of the predominant minerals glaucophane and lawsonite. Usually fine grained due to the rapidity & low temperatures of the mechanism involved. However, porphyritic varieties can be found. These particular samples come from the Isle of Anglesey, N. Wales and are supplied by weight in lots of 1 kilogram along with an information label.