Description

A beautiful sharp, glassy tourmaline from the John S. White collection with an important story to tell. This elbaite crystal formed first as a pink crystal and subsequently as the crystal grew, the crystal continued its growth as a green and slightly aqua-hued crystal (due to minor changes in the composition of the substrate from which it was growing) – this is the very well-known phenomenon that is often referred to as “watermelon tourmaline.” However, things become more interesting. After the crystal had formed, it was subjected to a solution that etched away part of the pink core but did not etch the green outer zone in the same way. The resulting specimen has an etched pink core, surrounded by a hollow, and then a great outer shell of lustrous green elbaite. Upon close inspection of the “bottom” end of this crystal, one can see on one side an etch pattern in the green, and also around the edges (it is not broken at the edges, it is crystallized). This pattern is typical when a solution both etches and allows recrystallization at the same time – the same phenomenon as seen, for example, in spessartines from the Navegadora Mine and heliodors from Volodarsk (Koroshiv Raion), Ukraine. John wrote an article about this phenomenon in tourmaline, including this specific occurrence at the Pederneira Mine, in Rocks & Minerals (Sept/Oct 2015, vol. 90, no.5).

Even without the story this is a beautiful aqua-green tourmaline crystal with sharp faces and striations. In excellent condition, very minor chipping on one side just at the termination, and a chipped area on the bottom edge – underside as displayed. An exquisite piece.

About John S. White (click here)