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Country:Federative Republic of Brazil
Region:Southeast region
Province:Minas Gerais, Malacacheta
Locality:Teófilo Otoni
Latitude:-17.8500
Longitude:-41.5000
Altitude:1256
Time zone:UTC-3(-2DT)
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Alexandrites are mined sporadically in the Malacacheta. Cat's-eye chrysoberyl is readily available at Teofilo Otoni, albeit in very small sizes, mostly under 0.5 ct. Alexandrites are available, if you search hard enough -- also in smaller sizes. One excellent color-change alexandrite of about 5 cts. was shown at the offices of Stone World in Teofilo Otoni.
Teofilo Otoni located between the stony hills and rocky mountains that are so characteristic of the landscape of the state of Minas Gerais, is Brazil's most important commercial center for colored gemstones, where about 55 percent of the country's output is brought to be sold. It is the beating heart of Brazil's colored gem trade, the town where production from hundreds of small mines dotting the region comes to be bought and sold. Driving through the region, it's common to see tunnels cut into the hillsides -- or, more correctly, the telltale white of the waste rock dumped outside the mine. These are all garimpeiro operations, some literally located in people's backyards.
Most famous chrysoberyl deposits, spread throughout the 1,800 hectares of the Faísca and Crisolita Basins. The cat's-eye chrysoberyl is about 30 percent of the rough found , although only 10 percent of that is good color. Few years ago, Brazil's environmental agency (IBAMA) shut down the Duarte & Bastos's mine for polluting the local stream and deforesting the region, which can cause serious erosion problems. Now, with only a dozen or so miners left, they're allowed to mine on a limited basis while they implement a 20-year plan to replenish the vegetation and build dams to remove soil sediment from the water.
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- V.B. Pinheiro. M.S. Baslio. K. Krambrock. M.S.S. Dantas. R. Paniago. A.L. Assunção. A.C. Pedrosa-Soares. The cause of colour of the blue alexandrites from Malacacheta, Minas Gerais, Brazil. Journal of Gemmology. Vol. 27. No. 3. pp. 1
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