This is a Ben Zuckerman suit, in a traditional menswear fabric- pinstriped wool but with feminine details like a small, dainty collar, mother-of-pearl buttons and three quarter length sleeves. The suit is tailored for a woman- you can see the darts at the bust to give the jacket feminine shaping.
The suit jacket is edged in black ribbon which is quite striking.
Photos courtesy of PurpleMonkeyDishrag.