Just a note on how nozzles are made, they are machined brass usually. They can wear pretty significantly over their lifespan too, especially if you run harsh materials (glow in the dark is harsh enough that a brass nozzle might not last a single print).

There are hardened steel nozzles, but even those are a wear item, they just wear slowly. As I said somewhere else, it's like trying to chase down a ransom note by analyzing the shape of the lead of a pencil that may have been used to write it. Just using it changes the properties.