Scintillation

[Diermint]

Scintillation is sparkle. The tiny flashes of light noticeable in a diamond when the observer moves his/her head.

 

[niceice]

Scintillation may also be described as the flashes of brilliance and dispersion (reflected white light and colored flashes or fire) that are seen in a diamond when either the observer or the diamond is moving. Thus scintillation may be witnessed when the observer moves his or her head or from across the room as a person walks by with their diamond ring...