Quern-stone

A quern-stone is a stone tool for hand-grinding a wide variety of materials, especially for various types of grains. They are used in pairs. The lower stationary stone of early examples is called a saddle quern, while the upper mobile stone is called a muller, rubber, or handstone. The upper stone was moved in a back-and-forth motion across the saddle quern. Later querns are known as rotary querns. The central hole of a rotary quern is called the eye, and a dish in the upper surface is known as the hopper. A handle slot contained a handle which enabled the rotary quern to be rotated. They were first used in the Neolithic era to grind cereals into flour.

Design The upper stones were usually concave while the lower ones were convex. Quern-stones are frequently identifiable by their grooved working surfaces which enabled the movement of flour. Sometimes a millrind was present as a piece of wood (or other material), which allowed the cereal etc. to be added but still acted as a centering device. The upper stone sometimes had a cup-shaped area around the hopper hole with a raised edge. Most handstones have a handle hole on the upper surface, but one class of quern-stones have a slot handle which indicates that a piece of wood was placed horizontally and protruded out from the edge so that the operator could turn the stone by standing and using a rod vertically. One class of upper quern-stones has from two to three sockets for the rod used to turn them and this is thought to reflect the need to reduce wear and tear by having alternative points of contact when in active use.

Grain

Quern-stones have been used by numerous civilizations 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. The use of grinding stones for vegetal food processing, and possibly the production of flour, was widespread across Europe from at least 30,000 years ago. In early Mayan civilizations the process of nixtamalization was distinctive in that hard, ripe kernels of maize (corn) were boiled in water and lime, thus producing nixtamal which was then made into unleavened dough for flat cakes by grinding with a handstone on a saddle-type quern (metate). Quern stones were used in China at least 10,000 years ago to grind wheat into flour. The production of flour by rubbing wheat by hand took several hours. Due to their form, dimensions, and the nature of the treatment of the surfaces, they reproduce precisely the most ancient implements used for grinding cereal grain into flour. Saddle querns were known in China during the Neolithic Age but rotary stone mills did not appear until the Warring States Period. A prehistoric quern dating back to 23,000 BCE was found at the Longwangchan archaeological site, in Hukou, Shaanxi in 2007. The site is located in the heartland of the northern Chinese loess plateau near the Yellow River.

Other materials As well as grain, ethnographic evidence and Mesopotamian texts show that a wide range of foodstuffs and inorganic materials were processed using stone querns or mortars, including nuts, seeds, fruit, vegetables, herbs, spices, meat, bark, pigments, temper and clay. 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. The authors 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. Querns were widely used in grinding metals ores after mining extraction. The aim was to liberate fine ore particles which could then be separated by washing for example, prior to smelting. They were thus widely used in gold mining in antiquity. In Shetland, tobacco was not smoked when first introduced, but instead was ground up into snuff, and inhaled up the nose. Snuff-querns consisted of an upper and lower stone, fixed together by a central iron pivot. The quern was held on the user's lap, the eye of the quern was filled with dried tobacco leaves, and then the upper-stone was turned using the handle. The friction caused by the turning ground the leaves into a fine powder that built up around the edge of the lower-stone. Many snuff-querns had a small hole or cut made near the edge of the upper-stone, into which a pointed end of a lamb's horn was placed in order to turn the stone; an alternative to using a handle.

Incidental uses

Quern stones' ubiquity led to ancillary uses. For example, DeBoer, 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. Quern stones may have been used as improvised weapons, as mentioned in the Bible: "But a certain woman threw an upper-millstone on Abimelech's head, and crushed his skull." (Judg. 9:53 NRSV)

Manufacture The best type of stone from which to manufacture quern-stones 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. Quernmore Crag near Lancaster in England is named after the quarrying of millstone grit used to make quern stones in these parts. The names of the mountains of Whernside and Great Whernside in the Yorkshire Dales have the same origin. Rutter 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 him to argue that, despite their everyday, utilitarian function, they were also used as a status symbol. Research in Scotland has indicated that to a degree regional styles existed.

… excerpt ends here. Continue reading the full article.