Speculum feathers

The speculum is a patch, often distinctly coloured, on the secondary wing feathers, or "remiges", of some birds.
Examples of the colour(s) of the speculum in a number of ducks are:
Bright wing speculums are also known from a number of other birds; among them are several parrots from the genus "Amazona" with red or orange speculums, though in this case the colors are pigmentary and non-iridescent.