The Praeneste fibula (the "brooch of Palestrina") is a golden brooch, today housed in the Museo Preistorico Etnografico Luigi Pigorini in Rome, Italy. The fibula bears an inscription in Old Latin. At the time of its discovery in the late nineteenth century, it was accepted as the earliest known specimen of the Latin language. The authenticity of the inscription has since been disputed. A new analysis performed in 2011 declared it to be genuine “beyond any reasonable doubt".
More information on the Wikipedia page [1]