Glaucophane Schist thin section microscope slide exhibiting a clear fabric and a wonderful blue hue under plane polarised light. The slide shows the fine grained nature of this rock which is associated with the rapidity of its metamorphic trajectory but also the low temperatures which tend to retard mineral growth. 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, both in thin section and hand specimen comes from the presence of the predominant minerals glaucophane and lawsonite. This material was collected from the Isle of Anglesey, North Wales. Each section is made to 30 microns thickness and the glass is 46 x 27 mm in size with a cover slip. Supplied in a protective card sleeve with a label, ideal for microscopy and educational purposes.