Sir William Henry Bragg (2 July 1862 – 12 March 1942) was an English physicist, chemist, mathematician, and active sportsman who uniquely shared a Nobel Prize with his son Lawrence Bragg – the 1915 Nobel Prize in Physics: "for their services in the analysis of crystal structure by means of X-rays". The mineral Braggite is named after him and his son. He was knighted in 1920.