Microscope slides of baryte from Cumbria, UK, these slides display the crystal structure of the mineral on a microscopic level which assists in the identification of this mineral in other slides. Baryte is a barium sulphate mineral, sometimes spelt baryte, it has been extracted in UK for centuries often associated as a by-product of lead and iron ore mining (mining of the minerals galena and hematite). An unusually weighty mineral hence its old name 'heavy spar' derived from Greek. It is commonly used as a weighting agent in drilling fluids and muds to balance the hydrostatic column when drilling through over pressured formations to prevent blow outs. Each section is made to 30 microns thickness and the glass is 46 x 27 mm in size, supplied in a protective card sleeve with a label, ideal for microscopy & educational use.