The Crimson Topaz is a large distinctive South American hummingbird. It is the largest hummingbird of Brazil, second in size after the Giant Hummingbird. Males are notably larger, with iridescent crimson plumage and sparkling green throat. They are more spectacular-looking than the females. Belly and breast are metallic orange-red, wings are brown and maroon in the lower part. The long tail coverts are golden green. They have short, slightly curved beaks.