What is the name of puncuation use in mostly french names?

There isn't a specific punctuation mark used "mostly" in French names. However, there are two common punctuation marks used in French names:

1. Hyphen (-)

* This is used to connect two parts of a name, often indicating a double-barreled surname or a compound given name. Examples: Jean-Pierre, Marie-Louise, Dupont-Laval.

2. Apostrophe (')

* This is sometimes used in French names to indicate a dropped letter or a possessive form. Examples: d'Artagnan, L'Herbier, l'Etoile.

It's important to note that these are just common patterns, and there are many French names that don't use any punctuation at all. Ultimately, the punctuation used in a French name is determined by its specific origin and evolution.