Diamond in Kimberlite

A rare specimen of Diamond in Kimberlite from one of the Shengli Pipes in the Changma Kimberlite Belt of Shandong Province in far eastern China.  A colourless gemmy to translucent natural Diamond has a rounded form whose exposed face measures 6 x 4 mm, the third dimension remaining hidden within the kimberlite.  The Diamond is colourless containing some black inclusions and its surface displays detailed growth patterns encompassing a central negative relief trigon (a triangular habit observed in Diamond).  The kimberlite rock is fascinating in its own right, with a characteristic jumbled mix of constituent minerals ranging between pale olive green and dark greenish grey.  Kimberlites are thought to have formed anywhere between 150 to 450 km (93 to 280 miles) within the Earth’s mantle, where the temperature and pressure are suitable for Diamond formation.  A really great specimen that is full of interest from this very seldom encountered Chinese location.