Topic: Help required with diamond registration mark please (Richardsons Tazza comport?)

[LEGSY]

I found this little tazza and it reminded me of the frosted leaf pattern which richardsons i think used on some of there glassware i was excited to find a diamond registration mark on the inside but i am having trouble with working it out hope somebody else can see what i cannot, The mark seems to have a 6 at the top a 7 on the left an x on the right and a w on the bottom, The tazza is 4.5"tall and 7" wide the diamond is on the last picture.
Thank you for looking

[keith]

If I've got this right it's Percival Vickers & Co, 1868 

[LEGSY]

  Thanks Keith that a great reply and very fast i will make some more in roads into it with this i am sure.
 

[keith]

 

[agincourt17]

Percival, Vickers & Co. Limited RD 217727, registered on 6 March 1868 - Parcel 7.

See also https://sites.google.com/site/molwebbhistory/Home/registered-designs/percival-vickers-designs-by-date/percival-vickers-1868-1869

Fred.