In Madame Errazuriz or The Lady in Black, we see a striking portrait of a woman dressed entirely in black. The use of deep, rich blacks contrasts with subtle highlights that give her dress a sense of texture and depth. Her gaze is direct and confident, suggesting a strong personality.

The background is muted, allowing the figure to stand out prominently. The painting is executed in oil on canvas, a medium that allows for rich color and detail. Sargent's brushwork is smooth yet expressive, capturing the fabric's flow and the sitter's features with precision. The dimensions of the artwork are approximately 76 x 63 cm, making it a sizable portrait.

The composition is balanced, with the figure centered and the dark tones creating a dramatic effect. John Singer Sargent was known for his portraits of high society, and Madame Errazuriz is no exception. The subject, a Chilean socialite, was a prominent figure in Sargent's circle. An interesting fact about this work is that it showcases Sargent's ability to blend realism with a sense of elegance, making it a notable example of his style.

This painting is currently housed in the Museo Nacional de Bellas Artes (Chile).