Tanzanite was first discovered in Merrani, Arusha, Tanzania in 1967.

The local Maasai people believe that the earth was hit by lightning and ignited the “God’s Fire”, which scorched the crystals in the earth into shiny blue and purple gems, which are attractive tanzanites.

Tanzanite is a kind of epidote, which looks very similar to sapphire and has the same pleochroism as cordierite. It will change color in the process of light source conversion. Because of the scarcity of mining areas, the price has been very high and has become a hot star gem.

There is no technology to synthesize Tanzanite artificially, but most Tanzanites are colored by heat treatment, which has become an internationally recognized standard procedure.

Tanzanite is a new precious gem in the jewelry market. Its unique charm and beauty have quickly won people’s favor.

Tanzanian stone is mainly produced in Tanzania. In addition, the United States, Mexico, Austria, Switzerland and other countries also produce Tanzanite.

Basic Properties of Tanzanite

The chemical formula of Tanzanite is Ca2Al3 [SiO4] [Si2OH7) O (OH), and the composition can contain a small amount of Fe, Cr, Mn, V, etc.

It belongs to the orthorhombic system, and the crystal is columnar or tabular.

1) Mohs hardness: 6~7.

2) Cleavage: complete along {010}.

3) Density: 3.25~3.37g/cm.

4) Optical property: inhomogeneous body, biaxial crystal, positive optical property.

5) Refractive index: 1.691~1.718, birefringence: 0.006~0.018.

6) Gloss: glass luster.

7) Color: Tanzanite is blue, purple-blue, and others are pink, yellow-green, brown, etc.

8) Pleochroism: strong.

9) Transparency: most of them are transparent, while those with many inclusions are translucent.

10) Special optical effect: It can have a cat’s eye effect.

11) Origin: mainly formed by hydrothermal alteration and regional metamorphism, also found in contact metamorphic rocks, pegmatites and quartz veins.

Tanzanite stone

Legend of Tanzanite

It is said that ancient Africans respected the Tanzanite as a “magic stone to impart divine power”, and it was used as a prop and a pendant for your elders in special ceremonies, symbolizing “inspiration from gods”, “eternity” and “wisdom of ancestors”.

It is believed that it can raise human consciousness to a higher level, so it is considered to be the most suitable energy stone to wear.

In Africa, people have been convinced since ancient times that this stone can ease mental tension and bring stability.

Only in modern times was it selected as the birthstone of December at the same time as turquoise and lapis lazuli.

Basic characteristics of Tanzanite

Tanzanite is gem-grade epidote, a calcium aluminum silicate. Because the color of natural epidote is miscellaneous, it needs to be optimized.

Generally, the epidote is heated to change the valence of vanadium from trivalent to tetravalent.

After heating, it can become bright blue Tanzanite with purple hue.

Identification of Tanzanite

The most typical feature of Tanzanite is that it has a beautiful blue color, bright and even; no color band or growth pattern can be found, and it is bright blue under sunlight or white light source, and it will obviously appear purple under a yellow light source.

Tanzanite has glass luster, moderate relative density and medium weight.

The interior of Tanzanite is relatively pure and transparent, with few obvious defects and inclusions.

Even if it is a large crystal, it can maintain a high degree of clarity and transparency.

Tanzanite has a strong chromaticity. The colors in three directions are blue, purple-red and green and yellow, which are easy to observe.

Identification of Tanzanite and Similar Gemstones

Gems similar to Tanzanite mainly include sapphire, cordierite, spinel, tourmaline, kyanite, and zircon, which can be identified according to their gemological properties.


The relative density of sapphire is 4, which is higher than that of Tanzanite (3.35). Therefore, under the same volume, sapphire is heavier.

The refractive index of sapphire is 1.762 ~ 1.770, which is relatively higher than that of Tanzanite (1.691 ~ 1.700).

Therefore, the sapphire with good cutting has a strong glass luster. The Mohs hardness of sapphire with a stronger glass luster than that of Tanzanite is 9, and the hardness of Tanzanite is 6 ~ 7.

Magnification inspection shows that the sharpness of the edges of the sapphire facet is higher than that of Tanzanite.

Sapphire has obvious dichroism (blue green-blue or light-blue blue), which is different from Tanzanite’s strong tricolor (blue purple-red green-yellow).


Both Tanzanite and cordierite have obvious tricolor, but the color of pleochroism of cordierite is different: the tricolor of blue cordierite is none to yellow, blue-gray, or deep purple;

The tricolor of purple cordierite is light-purple dark-purple yellow-brown.

The relative density of cordierite is 2.61, which is lower than that of Tanzanite. At the same volume, Tanzanite feels heavier when touched by hands.

The refractive index of cordierite is 1.542 ~ 1.551, which is obviously lower than that of Tanzanite, so the luster of cordierite is slightly lower than that of Tanzanite and is not as bright as that of Tanzanite.

In addition, the weak absorption bands of 426nm and 645nm of cordierite are different from those of Tanzanite (595nm and 528nm).

Blue Spinel

The color of blue spinel is uniform with a slight gray tone, which is very different from that of Tanzanite.

Blue spinel belongs to a homogeneous body without pleochroism. There are many gas-liquid inclusions and octahedral small spinel inclusion groups in it, which is also very different from the internal characteristics of Tanzanite.

blue tourmaline

The differences between blue tourmaline and Tanzanite are mainly as follows:

The color is mostly green with more cracks and empty tubular gas-liquid inclusions;

The refractive index of tourmaline is 1.624 ~: 1.644, smaller than that of Tanzanite;

In addition, the absorption spectrum of blue tourmaline is generally absorbed in the red area, and there is a strong absorption band at 498 nm, which is also different from that of Tanzanite.


The output of Benitoite in the world is small, and its particle size is small. Benitoite is blue to purple, with the refractive index of 1.757 ~ 1.804 and the birefringence of 0.047, both higher than that of Tanzanite.

Benitoite has a strong dispersion of 0.044, and obvious back-faceted prismatic ghost and color band can be seen through magnification inspection.

Under short wave ultraviolet light, it can have strong blue-white fluorescence, which can be distinguished from Tanzanite.

Blue Zircon

The zircon after heat treatment is bright blue, sky-blue, or light-blue with a slight green tone, with strong dichroism (no to brown yellow blue), which is different from Tanzanite.

In addition, due to its high refractive index (1.925 ~ 1.984), high dispersion (0.038), and high birefringence (0.059), zircon shows a strong luster and fire color.

At the same time, when magnified, it can be seen that the double shadow of the faceted prisms behind the gemstone, which can be different from Tanzanite.

Evaluation of Tanzanite

The evaluation of Tanzanite includes color, clarity, cutting and weight.

As a kind of gemstone that is known for its color, Tanzanite color accounts for the highest proportion of value (more than 50%).

Tanzanite is best in bright blue, followed by purple-blue, gray-blue, etc. The color of high-quality Tanzanite should be pure, bright and uniform.

Generally speaking, Tanzanite with rich color has a higher value than light-color Tanzanite.


Inclusions and defects will affect the appearance and durability of gemstones. High-quality Tanzanite has a pure interior with high transparency, no defects or hard-to-see defects by visual inspection, no defects on the surface, and no or very few inclusions under a 10x magnifying glass.


Transparent Tanzanite is generally processed into faceted gemstones, such as emerald, oval, round diamond, etc. High-quality Tanzanite shall have a proper cutting and grinding ratio and good polishing.


With the same other evaluation factors, the weight of Tanzanite directly affects the price. The greater the weight, the higher the value.

Purchase of Tanzanite Tips

Tanzanite has become the public’s new favorite because of its distinctive color.

There are quite a few choices on the market, so you need to consider various factors when buying Tanzanite.

Buy according to your preferences and budget.

The price range of Tanzanite varies with the color, purity, weight and other factors. The richer the color, the better the purity, and the greater the weight, the higher the value. Tanzanite with high-cost performance can be selected according to personal budget.

Pay attention to the grinding thickness of Tanzanite

Tanzanite’s deep and pure blue with precise cutting, can show a quiet and elegant temperament.

In order to reflect the most beautiful color of Tanzanite, gem cutters and grinders will cut and grind the lighter Tanzanite into thicker layers to increase the saturation and concentration of color;

The darker Tanzanite is cut and ground thinner to reduce the concentration.

The jewelry made of Tanzanite can be of various styles, which is very suitable for wearing on various occasions.

The Tanzanite jewels worn by women are generally a large Tanzanite center stones with a small diamonds.

Combining these two kinds of gemstones further brings out Tanzanite’s beautiful color and texture.

When purchasing, you should consider whether the main and matching stone’s size and quality are in harmony with the material, design style and inlaying process of precious metals.

Well-designed Tanzanite jewelry can give people a sense of elegance and implication, showing a unique style.

Tanzanite Healing Property

Tanzanite belongs to the orthorhombic crystal system, which can bring powerful energy and has the quite special power to enhance inspiration.

In real life, if we feel that we are often underappreciated or underestimated, and our hearts are filled with unresolved disappointment and tears, we can use the energy of Tanzanite to rediscover our potential, be firm in our inner dreams, and teach us don’t need to be someone else, just to be ourselves.

How to use Tanzanite

Ordinary users can wear Tanzanite to enhance their intuition and make win-win decisions that are beneficial to themselves and others more quickly.

Tanzanite can help us find the direction and mission of our souls and improve our inborn energy.

When we are too insistent on our own beliefs to assess reality and make appropriate changes, Tanzanite can improve our ability to introspect and let us adjust our own ideas.

When to use Tanzanite

  • Enhance inspiration
  • When it is necessary to accelerate thinking
  • Want to pursue their dreams
  • Get support from others

How to clean Tanzanite

Purification mode

Except for the sunlight method, other purification methods are available


The main chemical components of Tanzanite are calcium, aluminum and silicon. Because the hardness is only 6.5, you need to be very careful when wearing and cleaning. It is best to avoid putting it in the ultrasonic cleaning machine for cleaning jewelry.

Another fascinating feature of Tanzanite is its pleochroism, sometimes dark blue, sometimes red-purple, and sometimes brown yellow, which will show different colors with different viewing directions or angles. It is very attractive.

Heating treatment is generally used on Tanzanite. Generally, the natural untreated Tanzanite has a brownish-yellow color, and this unpleasant brownish-yellow color greatly reduces the mysterious beauty of the Tanzanite. Therefore, the rough brown-yellow stone is heated to 500 degrees Celsius to remove the brownish yellow to make it a beautiful blue-purple color.

This heat treatment will permanently change the color of the Tanzanite, greatly increasing its value.

The American Gem Association (AGTA) lists Tanzanite, the blue Zircon and Turquoise as the birthstone for December. Generally, Western women wearing Tanzanite are regarded as a manifestation of self-confidence and maturity.