High Quality Content by WIKIPEDIA articles! USS Moonstone (PYc-9) was a coastal patrol yacht in the service of the United States Navy. She was built in 1929 as Nancy Baker by Germaniawerft in Kiel, Germany, later renamed Mona, and subsequently acquired by the Navy as the Lone Star on February 10, 1941. Renamed Moonstone and designated PYc-9, she was converted for Navy service in Jacksonville, Florida, and commissioned on April 10, 1941. She was named for the gemstone moonstone.