-Italian colliers Castore e Polluce. Named after Castor and Pollux, two brothers from Greek/Roman Mythology, these two ships were built in 1917 under the designation of "mineral transport steamers" and served throughout the rest of the First World War and the interwar years. During the Second World War, they were sunk by Allied bombing raids on Italian ports. The first was sunk in 1943, the second in 1944.
That's about all the info I could find, a special thanks to Charguizard and ABetterName, as well as the other members of the discord server who helped me refine my design so it could be posted here on the forums!