Firing colour

Fired colour 1200°C light cream light red white... 

Generally said, the iron content is responsible for the red firing colour and the calcium content for the yellow colour. When the iron content is low and enough aluminium oxide is present, the free iron(III) oxide will bind with the silicates to form yellow compounds. Table 11.2.1 lists the baking colour as a function of the proportion of the iron(III) oxide, aluminium oxide and calcium oxide masses. 

MASS PROPORTION Fe203 / CaO IN CALCIUM CONTAINING CLAY FIRING COLOUR... 

The firing colour was discussed in the paragraph on coarse ceramics. Colours are measured quite often in the plastics industry, but I have not be able to find out if the method applied there is also applied in the ceramics industry. It is certain,however, that colours are measured visually in the brick industry, i.e. colour charts are used as reference... 

PHLOGIUM — A species of Violet, so named because the blossoms, or flowers, have a certain fire-coloured aspect. 

Chemical Composition Particle Size Distribution Specific Surface Area. . Wet-to-Dry Shrinkage Dry Strength Base Exchange and Deflocculation Soluble Salts Fired Colour Vitrification., ... 

Green Strength Fired Colour Firing Shrinkage Vitrification, . ... 

Fired Colour Plasticity 1.6.4 Building Clays Occurrence Composition. . ... 

Physical Properties Particle Size Distribution Defiocculation Working Moisture Content Firing Shrinkage Fired Colour Vitrification. . 

Ball clays are variously described as blue , black or ivory , according to their colour the blueness or blackness is caused by the presence of much organic matter whereas ivory clays owe their colour to the presence of iron oxide. The colour of an unfired ball clay, however, is not necessarily any guide to its fired colour. 

The fired colour of a clay depends primarily on its percentage of iron oxide, the state of oxidation of the iron, the degree of subdivision, and the extent of vitrification. Calcium oxide and magnesium oxide are said to bleach the colour, and organic matter may lighten the colour by maintaining the iron in the ferrous state. 

Little need be said about the fired colour of fireclays. Because of the appreciable amount of iron oxide they contain, they fire buff to reddish brown in an oxidising atmosphere and so are not suitable for use in the production of whiteware. 

The fired colour of a clay is due principally to its content of iron oxide, but also depends on the firing-atmosphere (whether... 

Clay Particle smaller diam s ize (% than In eter) Working moisture content (% dry basis) Linea shrii ( r firing nkage %) 1 1 Fired colour for different temperatures j ( ... 

Cartridges, Signal Articles designed to fire coloured flares or other signals from signal pistols, etc. UN App. B, ICAO A2, lATA App. A... 

Brokes. Term used in the English ball-clay mines for clay that will not cut into balls such clay is generally of low plasticity and poor fired colour. Brongniart s Formula. A formula relating the weight (W, oz) of solid material in 1 pint of slip (or slop glaze), the weight (P, oz) of 1 pint of the slip. 

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