Bertrandite with Tourmaline
Miniature, 3.7 x 3.0 x 2.7 cm
Golconda pegmatite, Governador Valadares, Minas Gerais, Brazil
Ex. Kay Robertson

Bertandite itself is an unusual and coveted pegmatite mineral, but when combined with Elbaites, as in this specimen from the great Golconda Mine, you have a truly rare and exceptional combination. The Bertrandite crystals are pearlescent, gemmy to translucent, and clear crystals. The thickness in some places creates more of a whitish appearance, and the tabular crystals form almost a bowtie-shaped cluster from a certain angle. The intergrown Elbaites are gemmy, a deep glass-green, lustrous, and striated. The longest of these Tourmalines is 2 cm, and it is nicely terminated. Very few Bertrandite/Tourmaline combinations are known, from this location or any other. This is from the original finds of this material in highest quality, brought to market by Luis Menezes in the early 1990s. Unfortunately Kay's original label for this piece was lost, but we know that she bought quite a bit from Menezes and we know this is the older style (quite different that a comparably platy and thin, modern find from 2017). This is an extremely rare specimen from Golconda's past, and considered by many to be the best find of the species for decades. A highly significant miniature specimen of a very desirable species that I regard as best pocket of the material!