Beautiful Tanzanite - I don't think I've ever seen as rich a blue in a zoisite as this 10 cm specimen on matrix from the Merelani hills of Tanzania. While it has almost certainly been heated to bring out the colour (natural blues only happen when heat has been an immediate part of their geological adventure through deep time), the depth of saturation (pink for example is a light red) and perfection of tone (neither too light or dark) make this a gem to be admired.
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