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ALBrazil has and will continue to produce the most amazing array of the finest tourmaline specimens, the NE part of Minas Gerais containing the greatest concentration of complex granite mineral rich pegmatites that hosts many famous mines whose names (Pederneira, Santa Rosa, Jonas, Golconda…) bring to mind distinct specimens with unforgettable and distinct features making them instant classics - the best of them often regarded as icons of the mineral world. This beautiful tourmaline cluster came from the Cruzeiro mine, one the most significant gem-bearing pegmatites and renowned for its extraordinary crystals. The Cruzeiro deposit is a rare element LCT family pegmatite, derived from a parental magma rich in aluminium, and during later stage evolution, small granitoid plutons solidified and exsolved volatile rich melts. These were injected into structural openings and crystallised, at around 2-4km depth and a temperature range of 360-570 degrees C, crystallising around 500 million years ago. The pegmatites are symmetrical, each wall showing similar sequences of mineral formation and reflects how crystallisation progressed inwards from both sides, the amazing multicolour crystals forming in the inner cores in miarolitic cavities that gave them space to form. As an uncontaminated pegmatite, the compositional evolution of tourmaline can be seen to progress across the pegmatites and gives great insights into the evolution of the whole system itself – more than just ‘pretty’!
But back to this amazing specimen, it features gave the name to the “Lollipop” pocket in which they were discovered, a stunning almost ‘confused’ mass of intergrown long prismatic crystals with sharp terminations, transparency, and vividly bright hues from green to that vibrant pinkish-red termination that makes it both breathtaking and so distinctive. Crazy-good. Thanks Nick Stolowitz for letting me ‘borrow’ it for a while 👏🏻 #minerals #tourmalinecrystals #brazil #crystals #fineminerals #geoscience #naturesart #amazingnature #discovery #highend #collectible #lollipop #iwantone
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