This piece features a cyclic twin (1.5 cm) and a V-twin of chrysoberyl, var. alexandrite, side by side in mica schist. In excellent condition (there is an incomplete crystal below them, near the bottom of the specimen as I’d display this one). The alexandrite crystals are dark, almost black in appearance and need strong light to discern the colour and colour change – they are a dark green hue in sunlight or LED illumination and dark reddish black hue under incandescent/halogen. Great matrix alexandrite twins.
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About these Alexandrite Specimens
Specimens of chrysoberyl var. alexandrite have been known from the mines of the Carnaíba district since the early 1980s, and have been found intermittently since that time. The crystals are usually very dark – it is often a challenge to spot the colour, even with strong light right against the crystals themselves. Carnaíba alexandrites are remarkable for their sharpness, and in particular for their excellent cyclic twinning.