Glass color

Color. Many water samples have a yellow to brownish-yeUow color which is caused by natural substances, eg, leaves, bark, humus, and peat material. Turbidity in a sample can make the measurement of color uncertain and is usually removed by centrifiigation prior to analysis. The color is usually measured by comparison of the sample with known concentrations of colored solutions. A platinum—cobalt solution is used as the standard, and the unit of color is that produced by 1 mg/L platinum as chloroplatinate ion. The standard is prepared from potassium chloroplatinate (K PtCl ) and cobalt chloride (C0CI26H2O). The sample may also be compared to suitably caUbrated special glass color disks. 

The cadmium chalcogenide semiconductors (qv) have found numerous appHcations ranging from rectifiers to photoconductive detectors in smoke alarms. Many Cd compounds, eg, sulfide, tungstate, selenide, teUuride, and oxide, are used as phosphors in luminescent screens and scintiUation counters. Glass colored with cadmium sulfoselenides is used as a color filter in spectroscopy and has recently attracted attention as a third-order, nonlinear optical switching material (see Nonlinear optical materials). DiaLkylcadmium compounds are polymerization catalysts for production of poly(vinyl chloride) (PVC), poly(vinyl acetate) (PVA), and poly(methyl methacrylate) (PMMA). Mixed with TiCl, they catalyze the polymerization of ethylene and propylene. 

Stained glass colors. Addition of a selenium compound produces red glass, and an addition of a cobalt compound produces blue glass. 

Glass color Coloring metal Glass furnace environment... 

Cobalt glass, color, 7 331 CobaltCII) hexaaquo ion, 7 229 Cobalt hexahydrate, analysis, 7 237t Cobalt high temperature alloys, 7 223-224 Cobalt hydroxide, analysis, 7 237t Cobalt(II) hydroxide, 7 230 uses, 7 240t... 

Nickel has properties like cobalt s, and it was also used to color glass, coloring it green rather than blue. The name nickel is derived from German copper miners name for nickel ore, kupfernickel ( Old Nick s copper ). Copper ore and nickel ore look very much alike, and the miners believed that the nickel ore had been planted in mines by the devil to deceive them. 

Zirconium hydroxide is used in glass colorants. The compound also is used to prepare zirconium oxide, sulfate, phosphate, and other salts. 

Glass color Metal Ionic form environment... 

Of the important properties of glass, color is one of the most interesting. Color is usually achieved by the addition of various metal oxides. The strongest of these are titanium, vanadium, chromium, manganese, selenium, iron, cobalt, nickel and copper. Silver and uranium will give weak colors. Some of the rare earths are also used as colorants with sharp absorption bands in contrast to the broad bands given by most colorants. (4)... 

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