Charles Thomas Jackson (June 21, 1805 – August 28, 1880) was an American physician and scientist who was active in medicine, chemistry, mineralogy, and geology.

Born at Plymouth, Massachusetts, of a prominent New England family, he was a brother-in-law of Ralph Waldo Emerson and a graduate of the Harvard Medical School in 1829, where he won the Boylston prize for his dissertation.

In 1829, he traveled to Europe where he studied both medicine and geology for several years and made the acquaintance of prominent European scientists and physicians.

[9] In 1847, Jackson was appointed United States Geologist for the Lake Superior land district, which was about to become one of the major copper-producing regions of the world.

[4] Jackson is particularly remembered for his involvement in a series of often bitter priority conflicts that left their marks on the scientific and social scenes of his day.

[3] Jackson also made a similar priority claim (1849) for the discovery that the unusual native copper deposits of Lake Superior, contrary to all previous geological expectations, could be successfully mined, although at that time it was universally acknowledged that credit for that discovery belonged to the recently deceased Douglass Houghton, Michigan's first state geologist.

[16] By unanimous vote of the McLean Asylum Trustees, Jackson was hosted as a guest at the hospital at no charge for the entire duration of his stay as a recognition of his past contributions.

In an article published on the Journal of Anesthesia History, Ramon F. Martin and Sukumar P. Desai analyze Jackson's life from psychobiographical view.