woman 1800s - most likely London, looking for a date & poss origin

[AusFamily]

Looking for a date or other comments for this photo, which was probably taken in the mid - late 1800s? I assume Stanley Bros, 124 Brompton Rd, was in London. It was in my deceased grandmother's collection.
I am wondering from the style of dress the woman is wearing if she may be of French origin? Were beaded necklaces common for English women at the time? My great-great grandmother was supposedly born abt 1833 in France and fled to England with her family after the 1848 revolution, (her family were in the pottery industry so the story goes). She married my English great-great granfather, whom his family (also in pottery) shunned because he married a Catholic. They lived in Islington. He ended up working as a jailor. They immigrated to Australia in 1881. Apparently she was very beautiful, which is why he married her, so the family story goes.

[jim1]

This can be dated quite closely as Stanley Bros. were
at the Brompton Rd. address for just a short period,1870-3.
He dress style is typical of that period & the jet beads were
a popular accoutrement. They were also worn by some
as mourning attire.
She looks in her 20's.
As an aside for dating it's best to show the back of the card also.

[AusFamily]

Thanks Jim,
I will take those comments on board when looking at my tree and trying to pin down who it might be.
Unfortuneately the original of the photo is in another city, as I digitised the pics about 10 years ago at my father's house. If there was any info on the back I did always record it somehow, whether it be in the description of the photo or otherwise.
thanks again