Microscope slides of hornblende from Norway, these slides display the crystal structure of the mineral on a microscopic level which assists in the identification of this mineral in other slides. Hornblende is an amphibole mineral which is often black or very dark green in colour, with the green sometime only being visible under certain angles of light and is due to the mineral containing high amounts of heavy elements such as iron, magnesium, silicate, aluminium and more. Due to its platy cleavage, it is sometimes confused with biotite mica or pyroxene. Its contents results in it being a slightly dense mineral, it leaves a black to grey streak and has a vitrous lustre. 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.