The adventure in the GM's Kit, "Debts to Pay" has an Iridium mine as a location. I know my players will ask and I've not been able to find anything- what is the ore used for? Weapons, speeders, ships?
Iridium Ore
I'd suggest taking your cues from it's actual uses.
Because of its high melting point and resistance to corrosion, iridium alloys are often used in electronics, in machines that work at high temperatures, and in places where other metals might wear over time (like the bearings of a compass or a balance). It also has medical and scientific applications.