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Tanzaniteis a blue/purple gem variety of the gemstone Zoisite.  It is characterized by a stunning colour which is not unlike top grade Blue Sapphire at the better end.  The hue can range from a light violet blue to a strong and intense bluish purple or purplish blue.  Tanzanite is not particularly hard, having a hardness value of 6 to 6.5 on the Mohs scale. For that reason, it should always be worn carefully and never placed in an ultrasonic bath for cleaning or brought into contact with acids and heat etc.

Most raw crystals are actually a yellowish/brownish colour  though this can be  be made to disappear by the cutter if he heats the stone carefully in an oven under controlled conditions. This heat treatment  is a method of enhancement which is regarded as customary in the trade and the treatment is permanent.  However the raw stones must be as free of inclusions as possible, since otherwise damage is likely to occur.  In fact working with tanzanite can sometimes give even the most experienced cutter a bit of a headache, the cleavage of this gemstone being very pronounced in one direction. This exclusive gemstone is cut in every imaginable shape from the classical round shape to a number of imaginative designer cuts.

Tanzanite is a relatively new gem discovery having been found  in 1967 in an area of Tanzania called the Meralani Hills some 60 miles from Arusha.  The story is told that some local tribes people upon waking up in the morning noticed some beautiful blue pebbles in the ashes from their fire from the previous evening.  It is really only found in this one area and how long the deposit will be workable is unknown. It is very much in the jewellery spotlight at moment and there is a worldwide demand for good material.

Cleaning Tips:

  • Soak in lukewarm soapy water using a mild liquid detergent. Rinse with water that is the same temperature and dry with a paper towel or soft cloth. 
  • Avoid exposing your stone to sudden changes of temperature. This includes hot tubs, very cold water, and reaching into ovens and then going straight to a cold sink.
  • Do not wear when doing any type of physical labor. e.g. gardening

Tanzanite is said to be a calming stone. It is good if life becomes chaotic or extremely busy and one is starting to feel out of balance. It will bring you back into balance.