I haven't raised very many Marans to be able to tell who's a hen and who's a rooster. FeatherSite.com has a lot of pictures of Marans. http://www.feathersite.com/Poultry/CGK/Marans/BRKMarans.html
I have a Black Copper Marans hen that I thought was a rooster. I was going to sell her but...
I am using a Marans hen with my Wheaten Ameraucana rooster to get Olive Eggers. The Marans has increased the egg size and her daughter's size. I find that the Wheaten Ameraucana's eggs are smaller but a very pretty shade of blue. I just hatched out some Production Red/Ameraucana crosses. Again...
Does anyone in the WNC area have any Bantam Polish for sale?( Or upstate SC or eastern TN?) I have 7 hens and I need a rooster. Any color. I will take any age even unsexed chicks in the hope that one may be a cockerel. I could order some from a hatchery but I don't need 25 Bantam WC Blacks!