In 1967 a British geologist by the name of Campbell R. Bridges was looking for gemstones in the mountains in the north-east of Tanzania. Suddenly he came across some strange, potato-like nodules of rock. It was like a fairy-tale: inside these strange objects he found some beautiful green grains and crystal fragments. A gemmological examination revealed that what he had discovered was green grossularite, a mineral belonging to the colourful gemstone group of the garnets, and one which had only been found on rare occasions until then. It was of an extraordinarily beautiful colour and good transparency. The find made the specialists sit up and take notice; Tiffany & Co. in New York also soon showed an interest in the newly discovered green jewel. However, in spite of all efforts, it was not, at the time, possible to export the stones from Tanzania. But Campbell Bridges was not one to give up easily. As a geologist, he knew that earth strata bearing gemstones were not necessarily limited to one particular area, indeed that they could extend over much greater areas - and in his opinion the stratum he had found was just such a one. For the rock belt in which most of East Africa's gemstone mines lie is very ancient. It began to form many millions of years ago, while the continents were still very much on the move. At that time, the area concerned had actually been under the sea. The sedimental deposits between the continents were greatly compressed and folded as a result of the movement of the massifs. Through tremendous pressure and at high temperatures, the rocks which had been present originally were transformed. New, exciting, beautiful gemstones came into being - among them the tsavorite. Having said that, the tremendous forces of Nature damaged most of the crystals so badly at the time of their formation that today it is usually only grains or fragments which are found.

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