The Effect of Decolorizing Agent on the Optical Properties of High Iron Contents Soda-Lime Silicate Glass

The aim of this study is to decolorize the high iron content (more than 0.1 %wt Fe2O3) glass. The contained 0.13 wt% iron oxide (Fe2O3) soda-lime silicate is prepared by high iron content sand with 0.17 wt% of Fe2O3. Iron oxide in soda-lime glass presents in two forms, Fe2+(green) « Fe3+(yellow). In principle, high iron content sand is not suitable to produce tableware. Therefore, the glass manufactures require high purity of sand because they want to control the amount of iron oxide as low as possible, which usually tableware glass contains only small amount of iron oxide (0.01 - 0.04 wt% Fe2O3) to avoid iron effect (green color). The soda-lime silicate glasses is decolorized by three different agents, Neodymium oxide (Nd2O3), Manganese oxide (MnO2), and Tin oxide (SnO2) 0.125 0.25 0.50 1.00 and 2.00 %wt respectively. The glasses are melted twice in the platinum crucible and investigated of the optical properties by UV-Vis spectrophotometer. The results of the color in CIE L*a*b* system are found that glass containing MnO2and SnO2slightly changes to white shade, but still presents in green. However, the result of contained 1.00 and 2.00 %wt SnO2glasses is nearly cleared, the result of contained Nd2O3glasses are satisfied, and the contained 0.25 %wt Nd2O3glass is showed very clear. Anywise the color of glasses containing 1.00 and 2.00 %wt Nd2O3turned to blue. The reaction of glasses containing Mn and Sn occur according to the mechanism of chemical decolorization. The reactions was described by the following equation, Fe2++ Mn3+g Fe3++ Mn2+and Fe2++ Sn5+f Fe3++ Sn4+, but the reactions are limited and strongly depending on the redox equilibrium. For Nd2O3,the reaction presents according to physical decolorization, because the color of Nd2O3is stable in melted glass and it can dismissed the color of Fe2O3directly. Therefore, this method can apply for the tableware glass production with high iron content sand.

Fanthorp Inn State Historical Park (41GM79), Grimes County, Texas: Archeological Excavations, 1983-1989

This report summarizes archeological investigations conducted by the Texas Parks and Wildlife Department at Fanthorp Inn State Historical Park from 1983 to 1989. This work was necessary to accompany architectural restoration of the inn as it appeared during the period between 1850 and 1867. Since restoration was completed, Fanthorp Inn State Historical Park in Anderson, Grimes County, has been run as an interpretive site representing a transportation and communication center of the mid-nineteenth century. The archeological excavations were intended to evaluate the areas impacted by the architectural restoration and to determine the appearance of the grounds during the mid-nineteenth century. Attempts were made to locate and identify several outbuildings shown on an 1850 map of the inn, but only the kitchen was located in this manner. Also, areas of ground disturbance such as the locations of the septic system and utility trenches were investigated archeologically. As currently configured, the grounds are made up of the L-shaped inn building, a barn that houses restrooms and a display, a parking lot, fences and paths, the kitchen as represented by a stabilized foundation, and one cistern that has been rebuilt to its original appearance. This report, by Prewitt and Associates, Inc., summarizes the excavations from 1983 through 1989 and provides analyses of diagnostic artifacts (i.e., bottles and jars, pressed glass, other tableware glass, lamp chimney rim sherds, flaked glass, transfer-printed ceramics, marked ceramics, smoking pipes, marked spoons, coins, arms and ammunition, dolls, marbles, and artifacts believed to be associated with African American religious practices). In general, the assemblage reflects a typical nineteenth- and twentieth century site in southeastern Texas.

Refractories: Something Old and Something New

The earliest refractories for containing melts were quarried from natural deposits of limestone and dolomite. Today these two carbonate rocks serve important roles in the production of metal contact refractories. Early refractories for glass melting on the other hand were manufactured from clays and claystones. These materials are also still used extensively for the batch melting of glasses that are hand formed or blown into art and tableware. Glass contact refractories for the continuous (tank) melting of glass are often fired, cast into large shapes, and arranged in a soldier course which constitutes the sidewalls of the glass tank.In this brief exposition of refractories technology and allied research, the articles by B. Brezny, T.F. Vazza and T.A. Leitzel, and by T.S. Busby cover materials development, selection, and properties of the systems which have evolved for the efficient melting of steels and glasses. As such they relate to extremes of technological flux in the processes for the manufacture of steel and glass, respectively.The continuous melting of large volumes of commercial glasses has been carried out in tanks equipped with reverberators for at least 70 years. The basic design of the overall system and of many of the glass fabrication machines for pressing, rolling, and blowing the glass has been constant since World War I. Only the introduction of the float glass method, the famous Pilkington process, for the production of flat glass, has interrupted the slow quiet progress in the technology of continuous glass making.