For many years I used the word “iridium” as a shorthand for tipping material. Everyone else did the same and we knew what we meant. Now and again some newbie would loftily inform me that these days it is rarely iridium that is used on nib points. Other metals from the platinum group would be more likely, they would condescendingly inform me. As I wasn’t allowed to actually kill the blighters I stopped doing it and now I always say “tipping material”.

My thoughts on the matter have been about the deterioration that affects some nibs, generally older ones. I have seen it described as a “pumice-like” appearance. The surface – and perhaps deeper than just the surface – is pitted. How does that happen? Platinum-group metals don’t suffer from oxidation or any other form of decay that I am aware of. Inclusions of other metals or materials have been suggested as a possible cause but I see that the temperatures that these hard metals are heated to, in order to weld them to the nib, are such that any other metal would be completely alloyed and could not exist there as separate particles. So what’s the explanation? How do we get these pitted, singing nibs?