Quern-stones are a pair of stone tools for hand grinding a wide variety of materials. The lower, stationary, stone is called a quern, whilst the upper, mobile, stone is called a handstone.
Quern-stones have been used throughout the world to grind materials, the most important of which was usually grain to make flour for bread-making. They were generally replaced by millstones once mechanised forms of milling appeared, particularly the water mill and the windmill, although animals were also used to operate the millstones. However, in many non-Westernised, non-mechanised cultures they are still manufactured and used regularly and have only been replaced in many parts of the world in the last century or so.
As well as grain, ethnographic evidence and Mesopotamian texts shows that a wide range of materials were processed using stone querns or mortars, including nuts, seeds, fruit, vegetables, herbs, spices, meat, bark, pigments, temper and clay (Wright 1992:87f). Moreover, one study analysing quern-stones noted that a number of querns had traces of arsenic and bismuth, unlike their source rocks, and had levels of antimony which were ten times higher than those of the rocks (Lease et al 2001:235). They concluded that this was probably due to the use of these querns in the preparation of medicines, cosmetics, dyes or even in the manufacture of alloys.
There are however, more surprising recorded uses of quern-stones. For example, DeBoer (2001:223), in his review of the traditional gambling games of North American tribes, reports that one of the games involved bouncing a group of split canes off a quern. A further example is recorded in the book of Judges (9:53; NRSV): “But a certain woman threw an upper-millstone on Abimelech’s head, and crushed his skull.”
The best type of stone to manufacture quern-stones from are igneous rocks such as basalt. These have naturally rough surfaces, but grains do not detach easily, so the material being ground does not become gritty. However, such rocks are not always available, meaning that quern-stones have been manufactured from a wide variety of rocks, including sandstone, quartzite and limestone.
Rutter (2003) was able to show, for the southern Levant, that basalt quern-stones were preferred to those manufactured from other rock types. Basalt quern-stones were therefore transported over long-distances, leading Rutter (2003:236) to argue that, despite their every-day, utilitarian function, they were also used as a status symbol.
There are a variety of types of quern-stone, with the two most common being the saddle quern and the rotary quern. The saddle quern is produced by grinding the handstone using parallel motions (ie pushing and pulling the handstone), which forms a shape looking like a saddle. These are the most ancient and widely used type of quern-stone. The handstones for saddle querns are generally either roughly cylindrical (not unlike a rolling pin) and used with both hands, or rough hemispheres and used with one hand.
As the name implies, the rotary quern used circular motions to grind the material, meaning both the quern and the handstone were generally circular.
Other forms of quern-stone include hopper-rubbers and Pompeian mills, both used by the Romans.