Editing Prussian blue (section)

===Color===
Prussian blue is strongly colored and tends towards black and dark blue when mixed into [[oil paint]]s. The exact hue depends on the method of preparation, which dictates the particle size. The intense blue color of Prussian blue is associated with the energy of the transfer of [[electron]]s from Fe(II) to Fe(III). Many such [[mixed-valence compound]]s absorb certain wavelengths of visible light resulting from [[intervalence charge transfer]]. In this case, red light around 680 [[nanometer]]s in wavelength is absorbed, and the reflected light appears blue as a result.

Like most high-[[Colorfulness|chroma]] [[pigment]]s, Prussian blue cannot be accurately displayed on a computer display.  Prussian blue is [[electrochromism|electrochromic]]—changing from blue to colorless upon [[redox|reduction]]. This change is caused by reduction of the Fe(III) to Fe(II), eliminating the [[intervalence charge transfer]] that causes Prussian blue's color.