According to her article in thepeerage, she was the daughter of Bess of Hardwick and married 7th Earl of Shrewsbury Gilbert Talbot. She had a daughter named Elizabeth.
From bbc.co; shadows filled in. This brought out her hanging sleeves (or cape).
Mary wears an enormously wide wheel farthingale canted upwards and accomodating the deep vee waist of her bodice.
Keywords: Mary Cavendish, Mary Talbot, Countess of Shrewsbury, Cavendish family, Talbot family, Countess, English, frizzy coiffure, jeweled headdress, necklace, draped necklace, square neckline, lace neckline ruff, lace bertha, long puffed sleeves, lace back-flared cuffs, deep vee waistline, wheel farthingale, fan