During the Predynastic Period, Egyptians mastered the working of even the hardest stone.
They especially favored attractively colored stones, like the porphyry, breccia, and obsidian shown here. To create the mace head (war club) and jar in this case, an artisan laboriously ground and polished the stones with increasingly fine abrasives. A method called flaking—carefully applying pressure with another stone—produced the serrated obsidian object.