Jane in the info I sent you is from the William Wheatcroft Harrison Co...WWH & Co. It's a silversmith in Sheffield, England, but I don't see anything about jewelry, only silver cutlery etc. So it may not be the same co. I sent you an email that has a photo of their mark.
What you need is to find a book with jewelry marks and what company they belong to. I found one site, but there was no WWH