English mineralogist and traveler who amassed valuable collections of minerals, manuscripts, and Greek coins and sculpture.

Clarke journeyed through England (1791), Italy (1792 and 1794), Scandinavia, Finland, Russia, Siberia, Asia Minor, and Greece (1799–1802). In all of these places he collected minerals and made observations of geography and climate as well as plant, animal, and insect life. In Sweden he collected manuscripts of maps as well as plant and mineral specimens. In Greece he collected some 1,000 ancient coins, vases, and statues—most notably, a colossal marble sculpture from the ancient city of Eleusis.

After his return to England Clarke became a minister in the Church of England (1805) and the first professor of mineralogy at the University of Cambridge (1808). His Greek marbles, which he donated to the University of Cambridge, are in the Fitzwilliam Museum. The Bodleian Library of the University of Oxford purchased his manuscripts, and Cambridge purchased his minerals after his death. His principal work was Travels in Various Countries of Europe, Asia, and Africa, 6 vol. (1810–23).