Red Gold Masonic Ring with Engraved Stone, Possibly Garnet

Hello,

I found the attached ring in a charity shop some while back and I am trying to figure out its provenance.

I have figured out it was assayed in Birmingham, that is 9 carat gold but the year mark, a small f in a square with cut corners, is not listed. The makers mark is S&G or S&C, do you know who this maker is?

I appreciate your help.

RW