I have compiled a list of sources for the elements that are available to the amateur chemist. Osmium will be discussed here.
Osmium is an interesting element. It is named after osme, which means stink. This refers to the tendency of powdered osmium to oxidize in air to form colorless, volatile, smelly, and highly toxic osmium tetroxide. Osmium itself is the densest element on the periodic table and one of the few colorful metals; it is light bluish, shiny, and brittle. Osmium is quite inert in bulk form but in powdered form it is quite reactive. It was discovered from platinum ores in the 1800s.
In element form: Some old photographic needles were supposedly made of osmium. Fountain pen nibs were sometimes made of osmiridium ore.
In compound form: No sources found.
I do not have any osmium at the time of this writing.