THE GOLD OF THAT LAND: Biblical Minerals & Rocks  

44.     lime

Hebrew: sîyd, boiling lime. Isaiah 33:12; Amos 2:1. The vale of Siddim (Genesis 14:3,8,10) was so named for its glaring white flats consisting of Lisan marl.

Probable identification:  biblical lime is Plaster of Paris or quicklime.

    Isaiah 33:12 probably refers to plaster of Paris, which is made in much the same way as quicklime, albeit more easily and at a much lower temperature (130^oC).

    Quicklime (CaO) is limestone calcined to calcium oxide by heating in a kiln at about 900^oC. Quicklime is not a mineral, of course, but a man-made product. When mixed with water, it gives off heat and sets as hydrated or slaked lime [Ca(OH)₂].

    The Mesopotamians burnt limestone for lime as early as the sixth millennium BC.

    Hareuveni suggests that the “well of Sirah” in 2 Samuel 3:26 was actually a limekiln made by kindling a fire in a hillside limestone pit filled with “seerim” or thorny shrubs. Making quicklime this way takes two parts of firewood and two parts of limestone burning at 900^oC for three to six days to produce one part of quicklime. This appetite for fuel contributed from early times to the denudation of the Middle East.

    The Egyptians did not use quicklime as mortar before the Ptolemaic period, beginning about 325 BC. The ancient Greeks built with lime mortar containing about 45% quicklime. The Romans improved on Greek mortar by adding quicklime to pozzolan or volcanic clay and aggregate to make their stronger mortar and concrete. Lime reacts with clay minerals to form a massive complex of interlocking silicates and aluminates which sets as cement, a durable artificial rock.

    Nari, a hard caliche crust covering most chalky surfaces in the Holy Land, is still burned today to make lime. It has also served as a building stone.

    Lime (CaO) is known as a naturally occurring mineral from Mount Vesuvius and its vicinity, near Naples in Italy, where it is a product of thermal metamorphism of limestone.

Sources:

        Ralph, Jolyon, 1993-2004. http://www.mindat.org/min-2401.html

        Tennisen, op. cit.; 97, 398.