(http://img692.imageshack.us/img692/9973/mallardq.jpg) (http://imageshack.us/photo/my-images/692/mallardq.jpg/)
Mallard ( Anas platyrhynchos 23") feathers are used for a lot of things. Usually a Drake is used, but one may also use a duck for a number of things.The underwings are very useful for the very even, brilliant white feathers,known as "satins". Which are the greater undercoverts.These can be dyed easily, and make very good wings, they were also often used on white winged on flies like the Coachman, various moths etc.They only have a very slight curvature. Bronze Mallard shoulders are used for lots of flies as, paired, bunched, or rolled wings. The metallic blue primary coverts are of course used for the Butcher slip wings, and one or two other flies like the "Heckham Peckham".
(http://img692.imageshack.us/img692/9941/mdw1.jpg) (http://imageshack.us/photo/my-images/692/mdw1.jpg/)
(http://img190.imageshack.us/img190/402/mdw2.jpg) (http://imageshack.us/photo/my-images/190/mdw2.jpg/)
Mallard primary flight feathers. Also known as "Grey Duck quills".
(http://img51.imageshack.us/img51/7043/aduckquills.gif) (http://imageshack.us/photo/my-images/51/aduckquills.gif/)
These are a "matched" pair, one from a left wing and one from a right. This is important when matching wing slips for various flies.
TL
MC