Glazed powder

The specific gravity of the coarser grains must be 1.69—1.76 for ungjazed, 1.72—1.80 for glazed powder. 

Cobalt oxide (ic) Lead oxide, yellow Sodium chloride glazing, powder Graphite glazing, putty... 

Gloss Point. When a layer of glaze powder is heated, a temperature is reached at which the surface changes its appearance from dull to bright this temperature has been termed the gloss point . (R. W. P. de Vries, Philips Tech. Rev., 17,153,1955.)... 

Y(lll), Cr(lll), Ru(lll), Fe(lll), Al(lll), Zn(ll)) 5 wt% glazed powders In conventional double-firing Ca0-Zn0-SI02 frit (1050°C). Composition, CIEL o 6 parameters (D65 illuminantand 10° observer), mineralizer s addition, and thermal treatment are Indicated for each pigment. 

Lead antimonate [13510-89-9] (Naples yellow), Pb2(Sb0 2> mol wt 993.07, d = 6.58g/cm, is an orange-yeUow powder that is insoluble in water and dilute acids, but very slightly soluble in hydrochloric acid. Lead antimonates are modifiers for ferroelectric lead titanates, pigments in oil-base paints, and colorants for glasses and glazes (see Colorants for ceramics). They are made by the reaction of lead nitrate and potassium antimonate solutions, followed by concentration and crystallization. 

Cobalt(II) phosphate octahydrate [10294-50-5], Co2(P0272 8H20, is a red to purple amorphous powder. The product is obtained by reaction of an alkaline phosphate and solutions of cobalt salts. The material is insoluble in water or alkaU, but dissolves in mineral acids. The phosphate is used in glazes, enamels, pigments (qv) and plastic resins, and in certain steel (qv) phosphating operations (see Enamels,PORCELAIN ORVITREOUS). 

Vitreous ceramics are made waterproof and strengthened by glazing. A slurry of powdered glass is applied to the surface by spraying or dipping, and the part is refired at a lower temperature (typically 800°C). The glass melts, flows over the surface, and is drawn by capillary action into pores and microcracks, sealing them. 

Schmelz, m. enamel, glaze fusion, melting, melt (Zinc) blue powder. 

Stannic oxide, SnC>2, is a white powder, insoluble in acids and alkalis. It is an excellent glaze opacifier, a component of pink, yellow and maroon ceramic stains and of dielectric and refractory bodies. 

Clark, R. J. H., Curri, L., Henshaw, G. S., and Laganara, C. (1997). Characterization of brown-black and blue pigments in glazed pottery fragments from Castel Fiorentino (Foggia, Italy) by Raman microscopy, X-ray powder diffractometry and X-ray photoelectron spectroscopy. Journal of Raman Spectroscopy 28 105-109. 

Stannic oxide (SnO ) is a whitish powder used as a ceramic glaze and polishing agent. 

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