Spear points

That largely depended on the region that was being inhabited by the tool users. The stone had to be able to conchoidally fracture, and leave no planes of separation. Through pressure flaking, the top of the stone is struck and fractured, removing material from the bottom until a shape and edge is formed.

Examples of stone use for this process include flints, chert, radiolarite, chalcedony or obsidian.