USS Carnelian (PY-19) was a converted yacht that patrolled with the United States Navy in World War II. She was named for carnelian (a semi-precious stone). Carnelian was built as the yacht Trudione in 1930 by Bath Iron Works, Bath, Maine for Ross W. Judson who was president of Bath Iron Works and Continental Motors Corporation. It was named after his twin daughters, Trudi & Ione. She was renamed Seventeen in December 1930. She was then purchased by the Navy on 13 May 1941 and commissioned on 7 June 1941 with Lieutenant Commander G. L. Hoffman, USNR, in command.