Studiolo di Cosimo I, Private room in Palazzo Vecchio, Italy

The Studiolo di Cosimo I is a small square chamber in Palazzo Vecchio with painted wooden cabinets built into the walls as storage units. The ceiling features frescoes depicting artistic pursuits and mythological subjects throughout.

Built around 1545 on the mezzanine next to Cosimo I's bedroom, the room was first fitted with wooden wall cupboards and a frescoed vault. In 1559 Giorgio Vasari redesigned the ceiling with the four Evangelists, while his workshop painted the Arts and Muses on the vault. Its traces were lost in the 18th century under the Lorraine and it was rediscovered only in 1908.

Cosimo kept personal documents, rare objects, medicinal plants and scientific curiosities here, and prepared remedies himself with complex procedures, sometimes sending them as gifts to other European rulers. The room's name Tesoretto, or little treasure, refers to this private hoard rather than to a public collection.

The studiolo is reached by two narrow staircases that start from Francesco I's studiolo, and visits run only in small guided groups through Muse's Palazzo Vecchio routes. The two studioli lie a short distance apart, so they are seen on the same itinerary. A third room frescoed by Bachiacca in 1545 is closed pending restoration.

Cosimo used the space as a workshop for preparing medicinal compounds that he gifted to rulers across Europe as diplomatic presents. This work earned him recognition as an experimental scholar, distinguishing him from typical collectors of the era.