The characteristic color that is determined by its wavelength as red, green, blue, purple, yellow, etc., and excludes white, black, and shades of gray in reference to the visible spectrum of light.
An isomorphous mineral of spinel group. A wide range of colors and shade of gemstone. Red-orange is named as flame spinel, an iron-rich dark-green to black, which is known as green spinel, pleonaste or ceylonite, grass-green as chlorospinel (iron-rich), b