Maker WWC -Sold, Rolled or Plated?

Hi,

I have a watch fob chain thing, with a number 9 and 375 on it (9 carot?!). Also what looks to be an anchor on its side (birmingham assay?) also has a letter t.

Can you tell me how to tell whether it's plated, rolled or solid?
Also before these hallmarks is a stamp WWC (makers mark?)
Would you have any info on this maker as well?
It belonged to my great grandad (I've just turned 40!)
thanks in advance.