...probably going to get my ass kicked but... I do have some native (ie as found in nature)osmiridium, or, as it is 'properly' called now "Ir-rich Osmium" for sale:
Os 57.89%
Ir 40.11%
Pt 0.87%
Ru .33%
Rh .25%
Fe 0.87%
...was the results of 5 analyses done by New Orleans Uni.
I have even got individual mm-sized hexagonal xls of this stuff .
It ain't cheap, and purified Johnson-Matthey stuff is a fraction of the price, but native stuff is rare.
If anyone is interested, I can get you more info/prices.
btw - I do NOT intend to solely use the forum for plugging sales, it is just that I am dispersing some of my element collection and this stuff (in its native form) seems to be be almost unknown to collectors. We've all seen the bluish shiny pellets - this stuff is flattened brilliantly lustred flakes - very odd!!