Most species show some green or bronze iridescence to the upperparts, but this is far less conspicuous than that of many other hummingbirds.
These white areas - especially on the pedipalps - have a nacre-like iridescence.
The interior of the shell is pearly with pink and green iridescence.
The pearly iridescence is often visible through the shell.
They have a layer of dark pigmentation just below the surface on each scale that enhances the iridescence.
The hindwings are similar to the forewings in color though less lustrous and with more purplish iridescence.
A trademark of swamp kauri is deep, shimmering streaks of iridescence, called white bait, found in some of the wilder grain patterns.
The under parts of these species lacks iridescence.
