TOURMALINE - The Story of a Great Find

The Morro Redondo Tourmaline Mine

This is the story of the largest occurrence of  Tourmaline in the history of Brazilian gem mining; the Morro Redondo Tourmaline deposit in the State of Minas Gerias, Brazil. The deposit was first discovered in 1992 near the village of Morro Redondo, in the Northeast portion of the State of Minas Gerias. The first pocket was found about halfway up the side of a local mountain in a pegmatite dike. It contained a modest amount of gem blue Tourmaline. Then on the following rise, they found 3 more pockets of a larger size. Most of the black Tourmaline had terminated ends with a layer-like surface terminations running parallel to the "C" axis, creating a "Pueblo" effect.

The next pocket contained Morganite beryl crystals up to 2 kilos in size, consisting of very clean Peach to Bi-color material. It was at this point that a very unique treating process was discovered that gave inspiration to the later developments in treating the Tourmaline from this mine. This Peach colored beryl material was first heated until it turned colorless, then it was subjected to 450 megarads of Cobalt irradiation. The turned the beryl to various shades of Green. It was then reheated to a uniform pale Pink.

The final Tourmaline pocket from Morro Redondo was 10-15 meters square. They began accessing the pocket by sinking holes to a depth of 3 meters. The Tourmaline discovered was a Brownish to Pink "A" axis, often found complete in Bi-color Blue/Green and Brown/Pink; the "C" axis being a Red to Pink/Peach.

The bulk of the material was extraordinarily clean and well formed. With the exception of the Blue/Green side of the Bi-color pieces, as this end of the crystal is almost always lightly included. The junction where the two colors join is often included with a light to heavy silk in the stone. Many of these had enough silk to form a Gem Cat's eye effect. This pocket (they named it Elba) produced a record 47 tons of Tourmaline total from February 1992 to March 1996.The first 8 tons of tourmaline and other gems was seized by local authorities and auctioned for taxes to the Govenador Valadares firm of Miranda & Co. for $60/kg. During the middle of the most productive period in time, they tunneled in from the side and the entire top above the pocket collapsed and caved in. All along the sides and bottom of the pocket were matrix specimens of Tourmaline, Albite, Lepidolite, and Quartz. Although this magnificent discovery was only sparsely reported in the United States, this huge Tourmaline deposit dominated the gemstone industry in Brazil for almost 4 years. Sales of ton lots of low grade (heavily included) material were common. There were over 400 miners working at the site during peak production. The public squares and gem trading streets of Arasuai, Teflo Otoni and Govenador Valadares were smothered with small miners selling off their weekly production. Mine Runs went from a low of $60 initially to $150/kg in first week of July 1996. Clean needles under 1 gram in size went from as little as $200 per kilo to $4/gm (July, 1996). Larger sizes (up to 100 gram) began at $10-20/gm and now are scarce, selling at almost whatever the seller's asking prices. Material of all grades, although rising steadily in price, will continue on the market for many years, attesting to the massive task of sorting out and processing the tonnage of gem materials that were produced. This Tourmaline is preferably cut looking down the "C" axis, producing Strawberry-Red and Peach-Pink Stones. It is not unusual that commercially the finished stones are first heated to 600C to turn to colorless, then heated further to 680-700C to gain a Pinkish hue. The stones are then given 80-100 megarads of Cobalt irradiation to return a fairly uniform "hot" red color. Adjustments by heating are made to those that treat too dark on the final stage. So, after a several years of heavy production from the Morro Redondo mine, the large finds have been mined out and only small amounts are still coming out. The major production of gemstone rough production was in it's final stages in early 1997 and only then did it begin reaching the U.S. gemstone market in quantity. From its first introduction to present the cut stone prices appear to be stable at around $35-50/ct for Parcels of calibrated goods in New York. Certainly for many years to come, the Morro Redondo mine production will be the Pink Tourmaline of choice due to it's astonishing production and now widespread availability.

Most of the tourmaline we carry in our inventory, both pinks, blues and greens are from this historic Morro Redondo find. All of our tourmaline is natural, and none of the tourmaline we sell has been irradiated.

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