White opal glass

Phosphoric acid Nickel oxides and cobalt oxides An ingredient of white opal glass or promotes transparency to u.v. or opacity to i.r. when used with ferrous iron Brown, purple, deep blue... 

Marquis reagent. 1 ml of formalin solution in 10 ml of concentrated sulfuric acid. The reagent is poured over the chromatogram (which must be thoroughly dry) supported on a sheet of white opal glass. 

Jars Parallel side cylindrical containers bearing no shoulder. Used mainly for creams and ointments. May be white flint, amber or opal glass. 

Color is one of the most important as well as the most eye-catching characteristics of microscopically opaque objects such as paint. Color measurements are carried out using a single-beam technique (previously measuring a standard on a perfectly white reflective object as a pure barium sulfate tablet or a polished opal glass) with microspectrophotometers fitted with image-side monochromators with geometry 4570° (like J M Tidas diode array spectrometers and the Zeiss MPM 800-system). 

Cryolite. Natural sodium aluminium fluoride, NajAlF m.p. 980 C sp. gr. 2.95. Because of its low m.p. and its fluxing action, it is used in the manufacture of enamels and glass and in the ceramic coatings of welding rods. Opal glass is often made from batches containing about 10% cryolite a similar preparation is sometimes used in white cover-coat enamels. 

Milk Glass. Alumina and fluorspar is added to soda-lime glass to produce an opaque white glass, (cf opal glass ... 

VIS-NIR region of the spectrum (Fig. 5). White glass materials, commonly known as opal glass —the most familiar of these are the so-called Russian Opal (also known as MS-20 milk glass) and Japanese opal glass—are also frequently used by manufacturers of color measurement instrumentation (Fig. 6). 

If all particles in a gel are of very uniform size and they are packed in a uniform manner, sintering will only occur suddenly as a given temperature is reached and the pores are all eliminated at the same time. Her has observed such a phenomenon in uniformly close-packed silica spheres 200 nm in diameter (see section in Chapter 4 on synthetic opal). This white opaque gel shrinks quickly as a certain temperature is reached (1000-1200 C, depending on Na content) and is converted to clear nonporous SiOa glass far below its normal softening point. 

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