Is my mare silver?

she is a westphalian 10 y.o. mare. we are looking into breeding her and want to know if her silver tail and partial mane will be a dominant trait? She has three white leg markings, and her father is Rheingau (Rheinland- Pfalz- Zar) and Dam is Hapstutbuch line (Westphalian)

To my knowledge there is no silver gene in those breeds so what she is showing is not truly silver but likely either "baby flaxen" or "gulastra plume" and would most likely not show in her foal.

Can you post a photo of your mare or her sire and dam?