The last Medici left the Florentine Diamond to Tuscany, the Habsburgs took it to Vienna, and it surfaced in a Quebec bank vault in 2025

The Florentine Diamond is a yellow stone of about 137 carats. The traveller Tavernier saw it among the Medici jewels in 1657. The Medici line ended in 1737, and Tuscany passed to Francis Stephen of Lorraine, husband of Maria Theresa. Tuscany's regional government says the stone appears in a 1740 annex to the last Medici's 1737 will and in an inventory of jewels "united to the State," which would keep it in Tuscany. It went to the Habsburg treasury in Vienna. In 1918 the last emperor, Karl I, went into exile in Switzerland with the family jewels. Italy claimed the diamond under the Treaty of Saint-Germain. In 1923 the Reparations Commission said Empress Zita could dispose of the stones as she saw fit. For a century the family did not say where the stone was. In 1940 Zita fled to Canada with the jewels in a cardboard suitcase. On 6 November 2025 her grandsons announced that the diamond had been in a Quebec bank vault since 1940. The jewels were placed in a Canadian trust for Zita's descendants. In December 2025 Tuscany's governor said the diamond belongs to Tuscany "not morally, but materially." Austria set up a commission on ownership. The jewels went on display at the Musée national des beaux-arts du Québec, Quebec City, in September 2026.