A previously unknown drawing by the German Renaissance artist Hans Baldung Grien has been rediscovered in a wooden box belonging to the family of the woman who sat for the portrait 500 years ago. Drawings by Baldung are extremely rare, with only a handful known in private collections. One with a direct-line provenance by descent from the original sitter is an unprecedented find.

Born in 1484/5 in Schwäbisch Gmünd to a family of academics, lawyers and doctors, Baldung broke the mold by eschewing university in favor of training as an artist. Between 1503 and 1507. he was a student of Albrecht Dürer in Nuremberg and became so trusted by his master that by the end of his training, he was running the daily works of the studio. It was in Dürer’s workshop that he was given the nickname “Grien,” because of his preference for the color green in his personal style and art. He adopted the monicker so thoroughly that he integrated it into his signature monogram, HGB.

He established his own studio in Strasbourg in 1510. Like his mentor, Baldung was multi-talented, excelling as a painter, printer, engraver and stained glass artist. By the time he made his best-known work, the 11-panel polyptych for the high altar of Freiburg Minster, he had garnered wide acclaim for his embrace of vivid color and eccentric approach to much-visited traditional religious subjects. Much less traditional was his treatment of profane motifs of witchcraft, eroticism, death and time, which was frank and sensual to a degree that was unmatched by other artists in his time.

Once his reputation and fame were established with altarpieces and religious art, Hans Baldung Grien was commissioned to make portraits of royalty, aristocracy and wealthy elites of the Holy Roman Emperor. His portraits were not the meticulously detailed records of his sitters’ features and clothing that his teacher Dürer was famed for; Baldung focused on capturing his subjects’ characters.

He drew the portrait of Susanna Pfeffinger in Strasbourg in 1517, the same year he became member of the city’s Grand Council. She was one of his wealthy royalty-adjacent patrons. Susanna Pfeffinger was born in Sélestat, now northeastern France, in 1465, the daughter of the town’s mayor. She married Friedrich Prechter, a prominent Strasbourg banker and merchant who reached the pinnacle of commercial and social success. He lent money to Holy Roman Emperor Charles V, so the circles don’t get any higher than that.

The portrait was executed in silverpoint (a brass stylus tipped with silver) on paper prepared with bone powder, a technique of great refinement and delicacy favored by Renaissance masters. It required an incredibly steady hand with only the pressure of the stylus on the prepared paper determining the depth of shadow and light. Dürer, who taught him the technique, learned from his goldsmith father. This portrait is the only silverpoint drawing by the artist still in private hands.

On a small piece of paper roughly the size of a postcard (15.7 × 10.4 cm; 6.2 x 4 inches), Baldung depicted Pfeffinger in three-quarter profile, dressed in a high-necked dress and mantel, her head completely veiled and bonneted, her neck and jaw up to her lower lip covered with a chin cloth that tucked into the veil.

The family kept this precious little card for five centuries in their large archive. The portrait was recently found in a crate full of other paintings and brought to expert Arthur de Moras, partner at the Beaussant Lefèvre auction company, for valuation. He identified as a rare work by Hans Baldung Grien and the family is now offering it for sale at auction in Paris this March. The pre-sale estimate values it at 1.5 to 3 million euros (ca. $1.74 million to $3.5 million).