John Alden Smith was born on May 19, 1830, in Kennebec County, Maine.

He was a geologist, publisher, and editor. He was apprenticed at the age of 14 years to the Hallowell Gazette, where he acquired knowledge of the various details of the printing trade. He opened his printing shop and became an owner and newspaper publisher of the Bethel Courier. An interest in geology, mineralogy, and metallurgy prompted studies of the disciplines. In 1864, he relocated to Colorado and worked at first in the office of the Central City Miner's Register as a geologist, then for Noble Gold Mining Company and American Gold and Silver Mining Company. He was editor of the Miner's Register, a journal on mineral resources in Colorado. He was named Colorado Territory's first geologist in 1872. From 1874 to 1879, he served as superintendent of the American and Slide mines for the American Gold and Silver Mining Company in Boulder County. Smith was appointed Colorado State Geologist in 1879. Along with General Frank Hall, he opened an agency in Denver that examined and reported on mines.

In 1853, he married Amy Elizabeth Wiggins (1833–1895). He died on July 17, 1896, in Magnolia, Boulder County, Colorado.