In the revised classification to create monophyletic genera, the white-chested emerald was moved by most taxonomic systems to Chrysuronia.

The nominate subspecies has iridescent turquoise-green crown and cheeks and shining bronze-green upperparts that become coppery on the rump.

Its central tail feathers are coppery and the outer ones bronze to copperish with blackish bars near the end of their underside.

It is found in eastern Venezuela, Guyana, Suriname, and extreme northern Brazil's Roraima state.

The species inhabits a variety of landscapes including rainforest; semi-deciduous, gallery, and secondary forests; scrublands; savanna; and some cultivated areas.

[9] The white-chested emerald forages for nectar at a variety of flowering plants and trees; species in at least nine families are known to be sources.

In addition to nectar it feeds on insects captured by hawking from a perch or by gleaning from vegetation.

It makes a cup nest of plant fibers with lichen on the outside and typically places it on a horizontal branch between 1 and 7 m (3 and 20 ft) above the ground.