Painting the metal of a Victorian fireplace

[versioncity]

I have cleaned up a victorian fireplace and was going to give the cast iron parts a coat of black paint.
I bought some 'Rustins heat resistant Black paint' to do the job but have just noticed they also do a 'High heat' version as well.
Should I be using the latter one as presumably it is more resilient?

 

[Wayners]

Some use stove and grate polish. Mostly for old black iron.
Maybe you should use wood burner spray paint.
Clean with meths and wire wool.
Spray