With working on my site and the pandemic’s disruption of available blue tourmaline rough, my tourmaline world has become more uncertain and less productive. Still I want to share a long awaited color event that helps keep me on the quest for more beauty in tourmaline gemstones.
Rich, but not dark, vivid blue tourmaline is in nature’s basket of tourmaline’s treasures. I have seen flashes of it down the c axis of a limited number of Indicolites, but the geometry and or the darkness of the rough precluded a true expression of the intense vivid blue of the axis.
I have had limited, partial, success with an oval cut from a pebble that had the c axis parallel to the ends of it rather than perpendicular to the sides. It is darker and included, but the a/b axis which is much lighter flashes in the moderate light, while the blue I crave dominates in the bright sunlight. The other example is a long ratio emerald cut that is blessed with small darker blue ends. Despite being heavily included and of little value, I had it tested for copper. It had none, but I wanted to be sure only iron was responsible for its color. And now for the subject of this post.
The broken tourmaline crystal was a little less than a gram and present a moderately toned blue that always accompanies the vivid blue of my quest. As I turned the cobbled crystal to see the hidden c axis, I expected it to be closed, but a good amount of pure vivid blue pierced the darker tones.
Now the question became how to cut the optimal indicolite gem from a relatively stout section of a crystal that had a moderate length to width ratio. An emerald cut is the first cut that comes to mind, but the crystal had spit down the middle, parallel to the c axis for just half of the crystal’s length. Grinding down the crystal to the thickness of the split section would waste a great deal of the meat of the rough and make only a small gem. If I cut a round out of the thick end with its table perpendicular to the c axis, would it be too dark?
Out came my diamond saw and off came the thin end. I was going for the blue whatever yield I would get. I ground a flat seat of wax on the end of a dop stick and epoxied the preformed rough both level and centered. Using the standard angle of 41 degrees for the pavilion mains and 42 degree mains on the crown, I had just enough material to bring home a standard round brilliant.
Cleaned and boxed the .83 carat tourmaline gem flashes pure, rich, blue color. It is the stuff tourmaline lovers crave and a reward for continuing to work with more problematic rough during the pandemic.