Cobalt Green

Cobalt green

Cobalt green is an ambiguous term for either of two families of green inorganic pigments. Both are obtained by doping cobalt(II) oxide into colorless host oxides.

Cobalt

Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray metal.

Green

Green is the color between cyan and yellow on the visible spectrum. It has 295–350 different shades. It is evoked by light which has a dominant wavelength of roughly 495–570 nm. In subtractive color systems, used in painting and color printing, it is created by a combination of yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content.

Cobalt blue

Cobalt blue is a blue pigment consisting principally of cobalt(II) aluminate, CoAl2O4, made by sintering cobalt(II) oxide with aluminium(III) oxide (alumina) at high temperatures. It is used as a ceramic color, in automotive and industrial coatings, in scientific and medical imaging, and as a fine-art pigment. Its thermostability, chemical inertness, and lightfastness make it suitable for applications requiring a durable blue color.

cobalt green

Noun

1. Any of various green inorganic pigments obtained by doping cobalt(II) oxide into colorless host oxides.