Tanzanite – rare blue violet gemstone from Tanzania | MINERALS-STONES
Tanzanite – rare blue violet gemstone from Tanzania and natural tanzanite crystals
Tanzanite is one of the rarest gemstones in the world. It is a blue-violet variety of the mineral zoisite that occurs in only one location on Earth – the Merelani Hills area in northern Tanzania.
This exceptional gemstone is valued for its unique color, optical properties and limited origin. Tanzanite is relatively young in gemstone history, yet within a few decades it has become highly desired among collectors, investors and lovers of natural minerals.
What is tanzanite
Tanzanite is a transparent blue-violet variety of the mineral zoisite with chemical composition Ca2Al3(SiO4)(Si2O7)O(OH). One of its typical features is the ability to display different color shades depending on viewing angle – this phenomenon is known as pleochroism.
The color of tanzanite ranges from light blue to deep blue violet. The most valuable stones display intense saturated blue tones with violet flashes.
Discovery of tanzanite
Tanzanite was discovered relatively recently, in 1967 in Tanzania. According to historical sources, the first crystals were found by Maasai herders after a wildfire cleared vegetation and exposed mineral veins.
The mineral was later analyzed and introduced to the gemstone market under the name tanzanite, referring to its country of origin.
Origin – only Tanzania
Tanzanite occurs exclusively in the Merelani Hills area near Mount Kilimanjaro. The deposit covers only a very small geographic area of a few square kilometers.
This extremely limited location is the main reason why tanzanite is considered rare.
Natural tanzanite crystals
Natural tanzanite crystals are usually found in smaller sizes. Larger crystals are significantly rarer and highly valued by collectors.
Crystals typically have prismatic shapes and may show natural pleochroism, meaning they display different colors depending on viewing angle.
Heat treatment of tanzanite – standard gemological process
Approximately 99% of tanzanite gemstones undergo heat treatment. This process is standard and accepted in gemology.
Heating takes place at controlled temperatures and serves to enhance the blue color by removing brownish tones.
Natural unheated tanzanite exists but is significantly rarer.
Rarity of tanzanite
Tanzanite is considered one of the rarest gemstones of modern times. The deposit is limited and the resources are not infinite.
This fact contributes to long-term interest among collectors and investors.
Color of tanzanite
The most valuable stones show deep blue violet color. The color is influenced by crystal structure and trace amounts of vanadium.
Tanzanite and certification
Like other gemstones, tanzanite may be accompanied by certificates confirming authenticity. Evaluation of colored gemstones differs from diamond grading.
Tanzanite gemstone information
Tanzanite among blue gemstones
Tanzanite belongs among the most desired blue gemstones due to its unique color.
Tanzanite price
The price of tanzanite depends on size, color intensity and clarity.
Rare natural tanzanite gemstone
Conclusion
Tanzanite is an exceptional gemstone with unique origin and color. Because of its single locality, it belongs among minerals with limited availability.
Natural tanzanite crystals are sought after by collectors and gemstone enthusiasts worldwide.