This little cutie was captured in Tuscon AZ at Desert Museum hummingbird aviary. Unfortunately, flash was not allowed and the lighting was sub-par. I was fortunate to get as good a shot as I was. When the light catches the vivid purple gorget, it is amazingly brilliant.
Average weight: male 3.05 g, female 3.22 g. Female birds are larger than males.

The identifying description is:

Plumage
Adult male: Metallic green back, violet-purple crown and gorget with very long side throat feathers, green breast.
Adult female: Green back and crown, white breast, white throat with some black spots, buff sides, white tips on outer tail feathers.