Its value is determined by rarity - the finer the colour or clarity, the higher the price. Tanzanite can only be found in northern Tanzania Mr Lazier urged his fellow small-scale miners to work ...

Its value is determined by rarity - the finer the colour or clarity, the higher the price. Tanzanite can only be found in northern Tanzania Mr Laizer mined the stones, weighing 9.2kg and 5.8kg ...

would later introduce the world to this rare and extraordinary gemstone, naming it after its country of origin. Tanzanite's ...