Preaspiration, i.e. [hC], is a rare feature of stop production in the world’s languages that has been recently found to occur in Sienese Italian. We present a qualitative acoustic-phonetic description of voiceless geminate stops /p: t: k: / with preaspiration that occurred in a corpus of spontaneous Sienese Italian speech (6 speakers). We outline the different fine-grained realizations of preaspiration and discuss the findings in the context of our general knowledge of the phenomenon across languages