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 Post subject: A tale of two tourmalines poles apart.
PostPosted: Mon May 27, 2019 5:16 pm 
Gemology Online Veteran

Joined: Thu Sep 25, 2008 10:33 am
Posts: 833
Location: Mars PA
This post is just some personal thoughts about two tourmaline gems that are widely separated by tone and color, yet both glorify the beauty of tourmaline. Neither gem is common, yet their physical properties are far more important to me than their rarity.

The first gem of the unlikely pair is a 3.36 carat paraiba type/cuprian/African paraiba/paraiba tourmaline (#1088 on my website I purchased the rough well before copper was discover in Mozambique material, but I knew that it was exceptional as soon as I cut it. I love its cyan/blue green color, but it is not an exceptional color in tourmaline. It is the appearance of the gem's physical properties of brightness, glo-like quality and saturation that continue to amaze me to this day. It is cut in a deep emerald cut with four rows of facets on the pavilion (40 degree keel) and three rows of facets on the crown. It is eye clean (I check with my loop, but I don't support diamond-like grading of color gemstones). It has an excellent crystal that is the best I have seen in Mozambique material. In other words it is one of the brightest gems I have in my collection even though it is cut in a style that does not generally produce exceptional brightness in gems.

Now the second gem in the pair is certainly a more personal selection. It is a deep, good sized round of 11.69 carats. Its lightly toned body is what I have come to call wheat/ecru (slightly brownish orange/yellow and if it was not very big, it would not have any noticeable color at all. Just a want to be achroite. It is eye clean and has excellent crystal. The key to its placement with the paraiba is a result of its cut and quality of finish, not its color. Still it is a rare mixture of color/tone/saturation for a tourmaline and I doubt that many people would guess it was a tourmaline at first sight. The pavilion is cut with twelve horizontally split mains with culet angles of 41 degrees. The crown is cut with eight rows of step cut facets starting with a row of 55 degrees, next to the girdle, that extend 2/3 of the distance to the table. The remaining 1/3 of the depth of the crown is made up a second row of steep step facets, top off with a very narrow series of guard facets. To complete the crown I cut break facets between the girdle faces that level the girdle and reach just to the guard facets. I believe that the well worn pebble came from Mozambique with little fanfare.

Now why would I place these two gems together in my post. First, face up they are two of the brightest gems in my collection of tourmaline of many colors and second they look bright, for very different reasons. The paraiba would stir men's souls even if it was just cut for weight, in complete disregard of proper angles. While the wheat round (#692 on my website brucefrytourmaline) needs every cutting advantage, it can support, to shine. Off face up, by many degrees and the wheat becomes a common light colored tourmaline while the paraiba shouts out its glory. It does not need any particular viewing angle. It goes to show you that in the world of commercial cuts, paraiba can make it despite being a tourmaline, while a lowly tourmaline can compete only if it is given the effort to properly cut and finish the gem. Having a lower index of refraction should not limit your expectations for tourmaline, so get out there and a cut a beauty .


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