Rosalba Carriera (1673-1757) was a Venetian painter who rose to fame and fortune painting miniature portraits on the inside of snuff boxes. Stylish aristocrats from all over Europe, stopping off in Venice on their grand tours, clamored to have Carriera immortalize them or their lovers in a pocket-sized edition. Her most famous such works were a series billed as The Twelve Most Beautiful Women in Venice. No slouch at marketing was our Rosalba. Once she got famous she moved on to full-sized portraits like this, which is Maria Theresa, second Hapsburg Archduchess, 1730.
I haven't been able to find many of her snuff boxes, but here is one, a portrait of Horace Walpole,
This work, titled A Muse, is probably also a portrait of some noble person; the Getty calls such works teste di fantasia, "fanciful renderings of beautiful women with a mythological appearance." The velvety sheen comes from blended pastels, a technique Carriera perfected in her snuffbox days. The Getty calls it "18th-century air brushing." She had two artistic sisters who helped her keep up with the work load.
Cardinal Melchior de Polignac -- now there's a name that says "international aristocrat."
Caterina Sagredo Barbarigo
Charles Sackville, second Duke of Dorset.
In 1721 Carriera made a triumphant trip to Paris, where she painted dozens of portraits and was elected to the Academy by acclamation. Louis XV.
And the French painter Watteau, done on the same trip.