Verdelite

Verdelite is the green gem variety of elbaite tourmaline — the most common colour in which gem tourmaline occurs. Shades run from yellowish and grass green to deep forest and blue-green, coloured by iron and traces of chromium or vanadium in the brighter stones.

Properties

Verdelite is trigonal, hard (7–7.5) and cleavage-free, with the characteristic striated prismatic habit and strong pleochroism of the group. Chromium-rich bright green material is sometimes distinguished as 'chrome tourmaline'.

Occurrence

It crystallises in granitic pegmatites and is found in Brazil, Madagascar, Mozambique, Tanzania, Afghanistan and the United States (Maine, California). Verdelite frequently shares pockets with the pink and blue elbaite varieties rubellite and indicolite, and bi-coloured and 'watermelon' crystals combine green rims with pink cores.