In our current culture, formal attire is almost playing at dress-up, essentially a costume for an occasional party event – certainly not a serious and expected part of one's social life.
This portrait is a window into a very different world when a young girl had only to watch her mother, sisters, relatives and friends to learn what her own adult life would hold for her. The studied pose this girl has assumed for the camera may be the product of hours of practice before the mirror and may be in emulation of ones she has seen taken by others.
She may be no younger than thirteen or as old as fifteen, a mere child in our eyes though I doubt if she would agree – this moment in front of the camera is serious business. Judging by her arms, hands and the narrowness of her shoulders, I doubt if she is even five feet tall. This is formal wear but not the grown up evening wear of the ballroom. Her eyes seem to say she is a good and willing study in this business of becoming a woman by the lights of her time and place.
The photographer's mark on the cabinet card is so damaged that the only information is a New York locale. There is no identification of this woman-child. If we could see her in later life, I think we know we would recognize her.