Pecking and grinding is the ancient art of removing small bits from stone to produce stone tools and weapons, such as axes, banner stones, and spear points. An abrasive stone, such as a sandstone pebble, is used to rub the blank smooth. This is done on either a pecked or knapped blank. Yes, sometimes ground stone implements
were knapped into their rough shape first, and then ground smooth.
Choose a suitable stone for Pecking. Granite or basalt are the best choices but, other sedimentary rocks can be pecked, as well.Select a stone that has few, if any, large cracks, fissures, or other irregularities which would likely cause it to break or brake off in undesirable ways.
Pick a stone large enough a similar in shape to the finished product you hope to produce.
Ground or pecked stone tools are not usually made out of the same type of rocks as knapped tools are. The stone most suitable for grinding is typically not the stone most suitable for flaking. Granites, quartzites and basalts, which are not nearly as nice to knap as finer grained cherts and natural glasses, can be made into serviceable tools by pecking and grinding. Another example of stone suitable for grinding is soapstone (steatite or talc-schist), which can be shaped into a variety of forms, including lamps, bowls, or pipes. Inuit and their prehistoric ancestors are famous for their work in soapstone. Slate is also a common grindable stone. It can be ground into flat, sharp cutting and piercing tools.
Methods of Making Ground Stone Tools Pecking: This technique is pretty much what it sounds like. The hammerstone (which must be harder than the blank) is used to pound or 'peck' the blank into the desired shape. Its not as elegant or quick as knapping, but its pretty tough to knap a stone bowl or grooved maul, so you do what you have to. In his book Flintknapping: The Art of Making Stone Tools, Paul Hellweg suggests using a tree stump as a support for the blank. If you hold the blank in your hand, your hand will absorb a lot of the force that should be going into the tool. You are wasting energy. And if you use a rock as an anvil you are likely to shatter your blank.
Grinding & Polishing: This is the step which gives ground stone tools their name. An abrasive stone, such as a sandstone pebble, is used to rub the blank smooth. This is done on either a pecked or knapped blank. Yes, sometimes ground stone implements were knapped into their rough shape first, and then ground smooth. Slate works well for this. Its a little soft to make chipped stone implements from, but it fractures the same way as chert or obsidian does, so the blank can be shaped quite nicely by flaking. The blank is ground smooth and sharpened in the same way as one would sharpen a metal knife.