Noircir belong to the 2nd
group. Noircir is a common french verb.
Noircir is conjugated the same way that verbs that end in : -ir
Noircir is conjugated with auxiliary avoir
Noircir verb is
direct transitive, intransitive.
French verb noircir can be conjugated in the reflexive form: Se noircir
verb is a direct transitive verb, so passive voice can be used.