This specimen is really different – most Carnaíba alexandrites are rather flat, but the main cyclic twin here is quite blocky (2.5 cm x 1.3 cm). This main crystal is sharp and has some good lustre. In excellent condition for its size, the right hand corner (first photo, or, in second photo, oriented at bottom) is chipped, as are a couple of smaller crystals on the piece. The crystals are quite 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-purplish black hue under incandescent/halogen. This is a good-sized alexandrite.
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. Carnaiba alexandrites are remarkable for their sharpness, and in particular for their excellent cyclic twinning.