Not much is known about the Florence Art company.
Their address was 851 W. Washington Street, Chicago, IL 60607.
It is believed they were in existence from about 1959 - 1977.
Glitter lamps had silver flake and brass-plated bases. There were single, double and triple lamp variants. While not extremely rare, they are not common either. They tend to survive fairly well due to their sturdy construction.
Use no more than a 10-watt bulb in the little FA lamps.
Models included: Astro-Lite, Stardust Lite, Magic Lite.
http://vintageglitters.carbonmade.com/projects/61165 - from Jonas
Updated list and info from Jonas here: http://oozinggoo.ning.com/photo/florence-arts-other-oil-glitters
Image courtesy of Bryin