This specimen combines quartz crystals with balls of bladed hematite crystals. The quartz crystals are superb examples of “growth-inhibited” or “interrupted-growth” crystals. As the quartz crystals grew, hematite periodically interfered and interrupted the growth of perfect quartz crystals. However, for several of these crystals the interference was only partial, allowing the quartz crystals to resume their growth after the interruption, to be interrupted again, repeating the process. Looking closely at these crystals, one sees that the hematite did not completely cover the quartz – in some cases, the hematite interruptions are clear rings, not plates through the quartz. So cool! Where the hematite covered more of the quartz, less quartz could continue to grow – this is seen at the terminations of three of the crystals.
The large balls of hematite along the one side are comprised of very sharp thin crystals.
In excellent condition, very minor chips in a few spots. The standing quartz crystals that appear incomplete are in fact terminated, but in an interrupted fashion.
From the John White collection, this specimen can be displayed really nicely in more than one orientation. I personally like it best supported as in the first photo, but I think it looks super in all three orientations.