https://i.ibb.co/6myfPgD/image.jpg
To grind stone stone age people use other stones - and we have hundreds, perhaps thousends, of this old grinding stones left from that time. They can be fond in free standing stones, on stonesground and on mountains.
Quartz sand and water was used to grind out their forms and edges. To make the hole they use a piece of wood like a drill, Quartz sand and water - and a lot of time.
A old name of this grinding slits is "sword grinding slitses" in Swedish: svärdslipningsrännor.
Thomas
To grind stone stone age people use other stones - and we have hundreds, perhaps thousends, of this old grinding stones left from that time. They can be fond in free standing stones, on stonesground and on mountains.
Quartz sand and water was used to grind out their forms and edges. To make the hole they use a piece of wood like a drill, Quartz sand and water - and a lot of time.
A old name of this grinding slits is "sword grinding slitses" in Swedish: svärdslipningsrännor.
Thomas