This section is from the book "The Home Cyclopedia Of General Information", by Charles Morris. Also available from Amazon: Home Cyclopedia of Necessary Knowledge.
[Ger. kobalt; from kobold, a goblin.] A reddish-white metal, very tenacious, and very difficult to fuse; occurs in small quantities in meteoric stones, and is usually found combined with arsenic and sulphur. It forms three compounds with oxygen. One oxide imparts a deep -blue color to glass. This glass, reduced to powder, is used in producing the blue colors in porcelain, pottery, glass, encaustic tiles, etc. Chloride of cobalt diluted forms sympathetic ink.
 
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