Love fireworks? Here is a highly dispersive* gem with internal fireworks that will
truly make you say WOW!!
Round sphalerite weighing 19.80 carats and measuring 16mm.
* The separation of white light into its component colors. Some gems display fiery flashes when held and turned in the light, which is the result of dispersion of white light into its separate spectral colors. Diamond is famed for this quality, but a number of other gems (ie: demantoid garnet, sphalerite, sphene, zircon) are notable for this effect as well. Demantoid garnet (.057), sphalerite (.156) and sphene (.051) all have higher dispersion than diamond (.044)!