Osmium Alloy Used in Fountain Pen Tips
Alloy of osmium and iridium improves durability of fountain pens.
Osmium alloy is used for fountain pen points, with the alloy called osmiridium when osmium is predominant and iridosmine when iridium is predominant.
The most important thing for a fountain pen is that it feels smooth when writing, which requires a suitable resilience and smoothness of the pen tip. With excellent acid resistance and wear resistance, osmium alloy pen tips enable the same writing feel for years and years.