Dutch Silver can any one identify

I have some Dutch Silver recently left to me the markings are E(circled) GERO 90 G-Z
Would lik to know if real silver if so would it be worth getting valued

That silverplate mark was used by Gerofabriek NV, Zeist, The Netherlands.
Founded in 1909 as M.J. Gerritsen & Company.
In 1925 Gerofabriek became the official name of the firm.
The number 90 refers to the 90 grams of silver used to plate 12 spoons and 12 forks.

I think it is 12 dusin i.e. 144 pieces that was plated with 90 grams