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MOTTLED OR COLORED SILICA BRICK *
Author(s) -
Phelps S. M.,
Limes R. w.
Publication year - 1943
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1943.tb14462.x
Subject(s) - colored , brick , color difference , materials science , composite material , mineralogy , metallurgy , chemistry , computer science , computer vision , filter (signal processing)
A bstract During the burning of silica refractories, spots or areas of dark cream to a reddish‐brown color may develop in some of the brick or shapes. This is often called mottling, and its occurrence during the manufacture of the product cannot be definitely controlled. Questions occasionally arise as to whether the colored brick are of as good quality as the uniformly cream‐colored brick. No records are available to show or indicate that color as such has been a cause of shorter life or failure in service. Data are presented that were obtained from testing the mottled and light‐colored brick, and these show that there is no practical difference between them; consequently, color alone should not be a criterion for judging quality. The traces of iron present in the silica used are a necessary constituent in the formation of the color. The light‐colored product, however, contains the same quantity of iron. It is not entirely clear as to how the iron is present in the two types. Unknown conditions during manufacture are such that the traces of iron may be influenced to form either the light or mottled brick, but the process cannot be controlled. A considerable amount of experimental work is presented which shows the nature of the color behavior with comments on certain conditions that cause the color formation.