THE GOLD OF THAT LAND: Biblical Minerals & Rocks  


 

31.     glass

Hebrew:

    1. mar'h, mirror

    2. re'y, a mirror. Job 37:18.

    3. gilywn, Isaiah 3:23.

Greek:

    1. esoptron, mirror or looking glass. 1 Corinthians 13:12, James 1:23.

    2. katoptrizomai, to see oneself in a mirror. 2 Corinthians 3:18.

    3. hualinos, made of transparent glass. Revelation 4:6, 15:2.

    4. hualos, transparent glass. Revelation 21:18, 21.

Probable Identification:

    The Greek word hualos definitely refers to clear glass. The Hebrew and Greek terms in other references are not so specific, and rendering them as glass is anachronistic.

    Old Testament passages refer to polished metal mirrors. Silvered mirrors were unknown. An esoptron might be either polished bronze or glass. 

     The description of a "sea" or water basin made of glass mixed with fire in Revelation 15:2 suggests fire opal, although the evangelist probably never saw any fire opal.

Mineralogy:

    Glass is not a mineral because it is not crystalline.

    Lechatelierite is a naturally occurring glass formed when lightning strikes fuse quartz sand grains at temperatures of 1,800oC or more. It is usually cloudy or frothy, and the surface will contain inclusions of sand grains. An area of the Egyptian Sahara contains widespread lechatelierite lumps that may have formed during the aerial explosion of a large meteorite. The first atomic explosion at Alamogordo, New Mexico in 1945 produced artificial lechatelierite. Lechatelierite particles occur in all tektites, which are naturally occurring, small glassy objects that superficially resemble obsidian. However, tektites are chemically distinct and do not contain microscopic crystals of igneous rock minerals. Most tektites are about a centimeter in diameter. In form, tektites fall into three classes: splash-forms, ablated forms, and Muong-Nong forms. The different forms all reflect rapid cooling from a molten state and deformation by impact or passage through the atmosphere.

    Obsidian is a mainly-black volcanic glass with a conchoidal fracture and a more vitreous luster than chalcedony. Iron and magnesium give it a greenish-black color. Clear to grey and brown varieties also occur, and reddish-brown and brown flow streaks and spots are common.

Historical Background:

    Because obsidian blades are sharper and harder than steel, obsidian from Anatolia made its way in trade to Palestine as early as the ninth millennium BC, possibly in exchange for bitumen and salt.

    The Egyptians used obsidian from the earliest times onwards in weapons and tools, and then in beads, amulets, and ornamental objects. Most of their obsidian came from Ethiopia and Sudan. Trade in obsidian from the Aegean island of Melos began as early as 7000 BC. One of the necklaces found in the tomb of Tutankhamun includes a prominent pendant with a clear greenish-yellow stone identified as lechatelierite from the Sahara desert in Egypt.

    Spherical droplets of obsidian found in the United States are known as Apache tears.

 Mineralogy:

    Glass is not a mineral because it is neither crystalline nor naturally occurring.

    Obsidian XE "Obsidian:volcanic glass"  is a mainly-black volcanic glass with a conchoidal fracture and a more vitreous luster than chalcedony. Iron and magnesium give it a greenish-black color. Clear to grey and brown varieties also occur, and reddish-brown and brown flow streaks and spots are common.

Historical Background:

    Because obsidian blades are sharper and harder than steel, obsidian from Anatolia made its way in trade to Palestine as early as the ninth millennium BC, possibly in exchange for bitumen and salt.

    The Egyptians used obsidian from the earliest times onwards in weapons and tools, and then in beads, amulets, and ornamental objects. Most of their obsidian came from Ethiopia and Sudan. Trade in obsidian from the Aegean island of Melos began as early as 7000 BC.

    Spherical droplets of obsidian found in the United States are known as Apache tears.

    Samuel Kurinsky attributes the origin of glassmaking to ancient Mesopotamia and the fusing of the emerging technologies of glazing bricks and iron smelting. Furnaces invented by Hurrian smiths for smelting iron provided the high temperatures needed to produce molten glass in quantity by about 2400 BC. Although the Egyptians made beads of colored and opaque glass and faience (tjehnet) as early as 4,000 BC, the Mesopotamian glassmaking industry reached Egypt around 1500 BC. Early glass was made by melting a mixture of silica with fluxes of wood ash and ground seashell. The Egyptians acquired such skill in controlling the color of glass and faience that their brightly colored glass soon supplanted colored gemstones that were mined in remote locations, such as carnelian, amazonite, and azurite. The addition of copper oxides produced green glass; metallic copper produced a ruby-red glass; iron oxides yielded green, brown, or black glass; manganese made prized amethyst and purple glass, and antimony oxide made yellow glass.

Glassmaking subsequently spread through Phoenicia to the Mediterranean region. The use of clear glass in bottles and other vessels became common in Roman times after the Phoenician invention of the blowing iron permitted making much larger and thinner vessels than was possible by the earlier method of casting molten glass around a clay core. Roman records indicate that Alexandrian Jews had emerged as the leading glassmakers by early in the second century AD.

    Sources:

    Kurinsky, Samuel, 2002. First Glass. In Meinhardt, Jack, ed., The Origins of Things. Washington, DC; 29-34.

    Lucas & Harris, op. cit.; 403, 415-416.

    A Brief History of Glass: http://www.glassonline.com/infoserv/history.html


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