Hand tool - Neolithic tools | Britannica.com
Hand tool - Neolithic tools: The Neolithic Period, or New Stone Age, the age of the ground tool, is defined by the advent around 7000 bc of ground and polished celts (ax and adz heads) as well as similarly treated chisels and gouges, often made of such stones as jadeite, diorite, or schist, all harder than flint.
