These are lustrous quartz crystals with vibrant red phantoms, and they have a distinctive look under the lights, as if the edges of the triangular faces are highlighted. This is because the red phantoms are quite close under the crystals’ outer surfaces, and the outer colourless layer of each crystal is quite thin – when the light passes through the transparent outer layer, it casts brighter lines where the crystal termination edges are. In excellent condition, minor rubs. From the Tracy Kimmel collection, ex Desmond Sacco (with a label, indicating that the piece was found in 1998). This is intense red quartz!