A very easy species to sex visually. Cocks have a redish chocolate-brown body compared to the golden colour of the hen (cock left)

He also has much deeper purple cheek patches as well as a royal blue band across the forehead. Note the black chin. This is the key in identifying young cocks at the stage where both sexes looks like hens. The black will start coming through soon after fledging.

His brighter ear coverts are also more apparent when viewed from the top.

And the cock also has a longer, blacker tail with a brighter rump (cock left)