She isn’t a portrait of anyone in particular. Dutch painters called this kind of picture a tronie: a study of a face, an expression or an exotic costume, here a blue-and-yellow turban. Her glance over the shoulder and her parted lips make it feel as if she has just noticed you.

The famous pearl is barely painted at all. It is little more than a soft gray shape with one bright highlight on top and a reflection of her white collar below. Your eye fills in the rest.