Thanks guys!   Her maiden name was Sarah Bridge born 1834 in Hetton le Hole, Durham, married John Swinburn at 22/23 in 1857 and died in 1862 age 28 of scarlet fever.  I was thinking, given the arm across her shoulder that this would have been a wedding picture.  She does look very young but 23 could have been possible.  I cant see anyone else who would fit the bill in the family I have got on that side.  It's definitely a mourning locket because it's big and black.  I really had no idea whether people were having wedding photographs done in the late 1850s!