This beautiful gem is an aluminum oxide which also has varying amounts of magnesium, iron and zinc within it. It was discovered in the Musgrave Ranges of Australia in 1967 but it has also been found in Tanzania and Madagascar. The stone usually comes in a green colour but some of them have a bright purple colour. Musgravite is in the same family as the Taaffeite, another rare gem on our list and the only difference between them both is due to the differing magnesium content. At times, distinguishing the two can be very difficult. Musgravite is sold at a hefty price of $6000 per carat.
