Our understanding of Upper Paleolithic stone technology remains imperfect, partly because the retouched stone blades were probably not complete tools. There is now quite early evidence for the process of hafting, in which stone tools form only one segment of a more complex tool or weapon. Most stone tools that we recover were probably attached to a handle made from organic material. Some flint bladelets such as this 17,000 year-old specimen from Lascaux Cave, France still had adhesive, probably sap or pitch, clinging to them. So the stone tools that we find have forms which may have been suitable for a number of tasks, depending upon how they were mounted in their hafts.