This is a very fine specimen, a plate of mica schist hosting a sharp 1.6 cm cyclic twin of alexandrite, with a few smaller associated crystals. In excellent condition, no damage to the main crystal (some chipping and incomplete smaller crystals, but these aren’t the focus of this piece. The main crystal is really nice – great form, and because some of the mica has been successfully removed from behind it, one can get light in from behind and it is possible to discern the alexandrite hues. The on this one crystals are still dark, almost black in appearance and need strong light to see 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. Standing perfectly on its own for display as photographed, this is a great matrix 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. Carnaíba alexandrites are remarkable for their sharpness, and in particular for their excellent cyclic twinning.