During his first six years as Keeper of Minerals at the British Museum, Mervyn Herbert Nevil Story-Maskelyne tripled the size of the meteorite collection. He was also a driving force in the development of optical mineralogy - the detailed study of minerals and rocks under a microscope.
This microscope was designed by Maskelyne and built in 1863. It was the first to include a rotating stage for viewing minerals under cross-polarised light.
When light is polarised, it can only vibrate in one direction. The way the light interacts with a mineral helps reveal its underlying crystal structure, a property that cannot be determined by the naked eye. Mineralogists today still use cross-polarised light microscopy as a preliminary tool to identify and classify minerals.
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