Hi Sturdy
The image of your ancestor appears to be a Victorian mourning photo. The anchor around her neck is a heraldic, Christian and Masonic symbol of hope. In this case, it is a St. Clement's cross (St. Clement also being the patron saint of mariners) and biblically refers to Heb 6:19; 'If you fear, put all your trust in God: that anchor holds.' There are further biblical references to the anchor in St. Paul. For Freemasons, the anchor symbolises well-grounded hope and a well-spent life. The black and gold bracelet she is wearing would traditionally contain hair of the deceased in the locket. From what I can discern, it looks like she is holding a bouquet of violets, the Victorian death flower by virtue of its purple colour.
I did a search on SP for you and found that Margaret Martin (nee Docherty) died, age 62, in 1898. Thus, you can calculate the approximate year the photo was taken by her age, which appears to be about 30-35. It may well be that she was mourning a parent or child, as her husband, James Martin, died not long after her in 1898.
Cheers,
Rodeo