Corundum pseudomorph after Spinel

Item Description

The Spinel crystals from Mahenge are among the best examples of the species to be found in the last 20+ years in terms of size, color and quality. Many people are familiar with the pink to red Spinels from Mogok in Myanmar, and while both localities feature crystals with that saturated rose hue, they are rarely found on matrix like they are at Mahenge. This large thumbnail sized piece was found in 2010, and at first glance you might think it's only Spinel, but it's actually rare pseudomorph of Corundum (Ruby/Sapphire) replacing Spinel. The sharp, well-formed, euhedral octahedral crystal of Spinel has been partially replaced on the exterior by Corundum, showing a white-pink hue on the edges, but the interior still has the strong pinkish-purple colored Spinel. When backlit, there is a bit of an ethereal "smokiness" inside the crystal for a nice touch. No significant damage that I can see with the naked eye, but there are some areas of interrupted growth where the Spinel crystals grew up against the marble. For a final touch, the piece shows a pleasing red fluorescence under UV light.