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The largest tsavorite in the world was found at the border of the original block B tanzanite mining area (Block B extension), at a depth of 160 meters. The area is locally known as Karo. The uncut stone weighed 185 grams and was examined by Dr. H. Hanni of SSEF Swiss Gemmological Institute during a recent trip to Arusha. The stone was preformed and facetted at the Multicolour Gems office in Chantaburi and certified by Dr. A. Peretti at the GRS Gemresearch Swisslab in Bangkok. The impressive size and saturated color combined with remarkable clarity and transparency put this stone in a class of its own. According to Dr. A. Peretti's report, -- "One Magnificent Gemstone".
Even tsavorites over 2 cts. in size are considered to be rare so an amazing stone like this will certainly end up with a collector or in a museum. The stone is step cut with good proportions and superior transparency and measures 42.11 x 36.46 x 28.34 mm. The GIA color was graded as G 4/5 - G 4/6 (medium tone, strong to vivid saturation) using the GIA 324 color comparison set. Although difficult to verify, our research indicates that at 325.13 carats, this stone is the probably the largest and definitely the largest clean tsavorite in the world. In a smaller size, material like this would be much lighter in color but in such a large size, the tone darkens to that illusive jello green that every connoisseur of tsavorite asks for -- not too light and not too dark.
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