The Shining Sunbeam is a weird species that shows a dull cinnamon belly, throat and face, with a dark olive back and wings, which do have strong iridescence that can be hard to spot, but that is very peculiar with a purple to gold smooth transition. From all the hummingbirds observed at Termales del Ruiz, which is situated at 3,000 meters above sea level, this one was the smallest, but it was also relatively numerous. The bill is relatively shot and thin, being black for the most part. The vent is covered in white plumage.

Not featured here, this species only has iridescense on the back, not in the front of the body.

Though not as small as the woodstars, this one is smaller than most species found at Termales del Ruiz.