John Hoppner, R.A.

In the collection of the present owners for nearly a century.

William Gregor was a British clergyman and mineralogist who discovered the elemental metal titanium. In 1791, while analysing the minerals in a black sand that he had discovered in the Manaccan valley, Cornwall, he isolated the calx of an unknown metal, which he named 'manaccanite'. Later that year, Martin Heinrich Klaproth (1743–1817) discovered what is now known as the transition metal, titanium, in the mineral rutile. Believing this to be a new discovery, Klaproth named it 'titanium' after the Titans of Greek Mythology, but eventually it was clarified that Gregor had made the discovery first. Gregor was credited with the breakthrough, but the element kept the name chosen by Klaproth.