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William Hyde Wollaston (1766-1828), English chemist and physicist. During his studies in medicine he became interested in chemistry, crystallography, metallurgy and physics. The mineral wollastonite is named after him. Wollaston became wealthy by developing the first physicochemical method for processing platinum ore in practical quantities, and in the process of testing the device he discovered the elements palladium and rhodium in 1803. His optical work was important as well, where he is remembered for his observations of dark Fraunhofer lines in the solar spectrum (1802) which eventually led to the discovery of the elements in the Sun.