What is the chemical formula of the mineral used by the inventor known as 'The Wizard of Menlo Park' in 1895?
Scheelite: Scheelite is a calcium tungstate mineral with the chemical formula CaWO. Scheelite:  It was also used in radium paint in the same fashion as was zinc sulphide, and Thomas Edison invented a fluoroscope with a calcium tungstate-coated screen, making the images six times brighter that those with barium platinocyanide; the latter chemical allowed Röntgen to discover X-rays in early November 1895. Thomas Edison: Thomas Alva Edison (February 11, 1847October 18, 1931) was an American inventor and businessman, who has been described as America's greatest inventor. Thomas Edison:  Dubbed "The Wizard of Menlo Park", he was one of the first inventors to apply the principles of mass production and large-scale teamwork to the process of invention, and because of that, he is often credited with the creation of the first industrial research laboratory.
CaWO