Tanzanite, with its mesmerizing shades of blue and violet, is a gemstone that has captured the hearts of many. However, its growing popularity has led to an increase in the production of tanzanite imitations and synthetic versions. Distinguishing real tanzanite from fake can be a challenging task, but it’s essential for consumers, gem enthusiasts, and collectors. In this article, we will uncover the secrets of authenticity when it comes to tanzanite. We will explore the characteristics of genuine tanzanite, the common types of imitations, and practical methods to identify the real gem from the imitations.
The Allure of Tanzanite
Tanzanite is a variety of the mineral zoisite and is known for its striking blue and violet hues. It was discovered in the Merelani Hills of Tanzania in the 1960s and quickly gained popularity due to its unique and captivating colors. Genuine tanzanite can exhibit shades of blue, violet, and sometimes even a hint of pink or lavender. Its rich, velvety appearance and rarity make it highly prized in the world of gemstones.
See Also: What Is tanzanite known for: A Gemstone of Rare Beauty
Characteristics of Genuine Tanzanite
Before delving into the methods of identifying real tanzanite, it’s crucial to understand the characteristics that are exclusive to genuine tanzanite:
1. Color
The most distinctive feature of tanzanite is its remarkable color range, which includes shades of blue, violet, and purple. The finest tanzanite gemstones typically display a deep blue-violet hue with excellent saturation. The presence of pleochroism means tanzanite can appear different colors from different angles.
2. Transparency and Clarity
Genuine tanzanite is transparent to translucent, allowing light to pass through the gem. Clarity is essential, with high-quality tanzanite exhibiting minimal inclusions. While some inclusions are common, they should not be prominent or affect the gem’s overall transparency.
3. Refractive Index and Birefringence
Tanzanite has a refractive index of approximately 1.691-1.700, which is within the range of other transparent gemstones. It also exhibits birefringence, meaning it can split a single ray of light into two, producing doubling effects under magnification.
4. Hardness
Tanzanite has a Mohs hardness of approximately 6.5 to 7, making it a suitable gemstone for use in jewelry. However, it is relatively softer compared to diamonds, sapphires, and rubies, which have higher hardness ratings.
5. Pleochroism
Tanzanite is pleochroic, meaning it displays different colors when viewed from different angles. This is a unique feature of tanzanite, and the color change can range from blue to violet or purple.
Common Types of Tanzanite Imitations
As the demand for tanzanite has increased, so too has the production of imitations and synthetic versions. It’s essential to be aware of these common types of tanzanite imitations:
1. Synthetic Tanzanite
Synthetic tanzanite is created in a laboratory using chemical processes that replicate the conditions under which natural tanzanite forms. While synthetic tanzanite can closely mimic the visual characteristics of the genuine gem, it may lack the inherent qualities and value of natural tanzanite.
2. Glass Imitations
Glass is a common material used to imitate tanzanite. Glass imitations can display a blue or violet color, but they often lack the optical properties, pleochroism, and durability of genuine tanzanite.
3. Synthetic Spinel
Synthetic spinel, a lab-created gemstone, can sometimes be used as an imitation for tanzanite. Spinel imitations may exhibit a blue or violet color, but they can be distinguished from tanzanite through gemological testing.
4. Other Colored Gemstones
Some colored gemstones, such as blue sapphires or iolite, may be used to imitate tanzanite. While these gemstones can resemble tanzanite in color, their properties and refractive indices differ.
How Much is the Genuine Tanzanite?
The price of genuine tanzanite varies based on factors like size, color, clarity, cut, and origin. Smaller tanzanite gemstones can range from approximately $50 to a few hundred dollars per carat, while larger and higher-quality gems can surpass $1,000 per carat. Exceptional tanzanites with vivid, intense blue-violet colors and minimal inclusions command the highest prices. The origin, with tanzanite from the primary source in Tanzania typically considered the most valuable, also influences cost. Keep in mind that tanzanite’s value can appreciate over time, making it an attractive investment for gemstone enthusiasts.
See Also: Tanzanite Stones: Unearthing the Value Within
How to Tell Real Tanzanite from Fake?
Distinguishing genuine tanzanite from imitations requires a combination of observation, gemological testing, and, in some cases, professional expertise. Here are practical methods to help you identify real tanzanite:
1. Color Examination
Examine the gem’s color closely. Genuine tanzanite typically displays a range of blue and violet hues with pleochroism, meaning it may show different colors from different angles. Imitations may lack this pleochroic effect or display a more uniform color.
2. Optical Properties
Use a jeweler’s loupe or microscope to examine the gem’s optical properties. Look for doubling or fuzziness of the facets, which is a result of tanzanite’s birefringence. This doubling effect is not typically observed in imitations.
3. Inclusions and Clarity
While genuine tanzanite may contain inclusions, they should not be overly prominent or impact the gem’s overall transparency. Glass imitations and synthetic tanzanite often lack natural inclusions and may appear too flawless.
4. Refractive Index
Determine the gem’s refractive index, which can help distinguish tanzanite from imitations. Tanzanite has a refractive index of approximately 1.691-1.700. Use a refractometer to measure this value.
5. Hardness Testing
Perform a hardness test using the Mohs scale. Tanzanite has a hardness of approximately 6.5 to 7. While it is not as hard as sapphires and diamonds, it should not be easily scratched by common materials. Use a known tanzanite or other gemstone of the same hardness to perform the test.
6. Gemological Testing
For a definitive identification, consult a professional gemologist. They can use advanced gemological equipment, such as spectrometers and refractometers, to confirm the gem’s authenticity.
7. Certification
When purchasing tanzanite, especially higher-value specimens, ensure that it comes with a reputable gemological certificate from organizations like the Gemological Institute of America (GIA) or the International Gemological Institute (IGI). These certificates provide detailed information about the gem’s authenticity and quality.
Conclusion: Unveiling the Authenticity of Tanzanite
Tanzanite’s exquisite color and rarity have made it a highly sought-after gemstone. However, the surge in demand has led to the production of tanzanite imitations and synthetic versions. To ensure that you are acquiring genuine tanzanite, it’s essential to be knowledgeable about its key characteristics, perform careful examinations, and, when in doubt, seek professional gemological expertise. By following these guidelines, you can confidently identify real tanzanite and appreciate the unique beauty and allure of this extraordinary gem.
