Home › Pigments › Green Oxide of Chromium

Green Oxide of Chromium

This oxide is perfectly stable, and, as so many tints of it can be obtained, including the beaua minute, by which time the oil will be burned tiful vividian, it can be used in all vehicles, and off, to loosen the sample from the charcoal is perfectly permanent in fresco and silicious with a knife blade or spatula, in order that painting. Other chromium compounds are the flame may pass under as well as over and used in painting; the chromates of lead have against it. With proper care the lead will already been treated of. Chromate of barytes run into one button, instead of scattering over is a good, safe pigment; it is used under the the charcoal, and this is the reason why name of lemon yellow. It is permanent in the cavity above mentioned is necessary. A fresco and silicious painting. The chromates common stearine candle or a lard oil lamp generally are unstable colors, and, as there are furnishes the best flame for use of the blow- so many other good yellows, they should not pipe; the flame of a coal oil lamp should not be used as pigments. be used. 2702. The Ochres are earths colored by

2696. Zinc White (oxide of zinc) is a oxide of iron. The natural color of these permanent pigment; is not affected by sul- earths is yellow, but by burning they get phuretted hydrogen; does not form soap with darker, and some become red. Indian red, oils and fats, therefore it retains its opacity; red ochre, light red, etc., are all earths with does not decompose other pigments, and if more or less of the oxide of iron in them. All used with proper vehicles retains its white- the ochres are permanent and stable if they ness. It is the best and safest white that can have been well prepared. They may be used. It is most durable in silicious painting, as it forms chemical compounds with potash and silica. safely in every style of painting.. 2703. Colcothar is also an oxide of iron; it is very permanent, and generally useful as a