Tourmaline

This magnificent deep bottle green Tourmaline crystal is from the pegmatite deposit at Taquaral in Minas Gerais, Brazil. Measuring a splendid 7.7 x 3.7 x 2.8 cm, the prism forms an asymmetric triangular cross section and when viewed from its cleanly cleaved base, shows an outer rind of mid lime green surrounding a thick inner core of glassy deep bottle-grass green Tourmaline.  The prism faces a vertically striated and the termination is trigonal, but of a more complex trigonal form with multiple rotated faces.  Once strongly backlit the crystals becomes a superb intense bright chrome green mottled with darker green patches.  Two of the three principal termination faces are beautifully patterned with the most unusual mix of frosted and lustrous intergrown triangular markings, different to but reminiscent of Widmanstätten patterns in meteorites.  This is not a comparison I’ve ever written previously for a Tourmaline description!  An amazing Tourmaline from Taquaral.