What To Know
- This means that the color of a tanzanite can appear to change depending on the direction of light passing through it.
- Specific gravity refers to the weight of the gemstone relative to its volume, while refractive index measures the bending of light as it passes through the stone.
- Obtaining a gemological certification from a reputable laboratory is one of the most reliable ways to ensure the authenticity of a tanzanite.
Tanzanite, a captivating gemstone renowned for its mesmerizing blue-violet hues, has captured the hearts of jewelry enthusiasts worldwide. However, with the increasing popularity of this rare gem, the market has seen an influx of imitations and synthetic tanzanites. To ensure you’re investing in a genuine tanzanite, it’s crucial to be equipped with the knowledge to distinguish it from its counterfeits. This comprehensive guide will provide you with valuable insights and practical tips to help you ascertain the authenticity of tanzanite.
1. Color and Hue: The Essence of Tanzanite
The color of tanzanite is one of its most distinctive characteristics. Genuine tanzanite typically exhibits a vibrant blue-violet hue, ranging from deep sapphire blues to lighter shades of periwinkle. The intensity of the color can vary, with some tanzanites displaying a more saturated hue while others appear more pastel-like. Additionally, the presence of secondary colors, such as green or brown, can indicate that the stone has been heat-treated or is of lower quality.
2. Clarity: Imperfections that Reveal Authenticity
Tanzanite, like most gemstones, often contains inclusions or imperfections. These natural blemishes are a testament to the stone’s genuineness. Inclusions can range from tiny crystals and mineral deposits to fractures and color zoning. While some inclusions may be visible to the naked eye, others may require magnification to be observed. The presence of inclusions, especially in small quantities, indicates that the tanzanite is likely natural and untreated.
3. Pleochroism: The Color-Changing Phenomenon
Pleochroism, a fascinating optical property exhibited by tanzanite, allows the gemstone to display different colors when viewed from different angles. This means that the color of a tanzanite can appear to change depending on the direction of light passing through it. Genuine tanzanite typically exhibits strong pleochroism, with colors ranging from blue to violet to purple. The intensity of the pleochroism can vary, but its presence is a strong indication of the stone’s authenticity.
4. Fluorescence: A Reaction to Light
Fluorescence is another notable characteristic of tanzanite. When exposed to ultraviolet light, genuine tanzanite often exhibits a strong fluorescence, emitting a bright blue or violet glow. This reaction to light is caused by the presence of certain elements within the gemstone. The intensity of the fluorescence can vary, but its presence is generally considered a positive indication of the stone’s genuineness.
5. Specific Gravity and Refractive Index: Measuring Physical Properties
Specific gravity and refractive index are two physical properties that can be used to identify genuine tanzanite. Specific gravity refers to the weight of the gemstone relative to its volume, while refractive index measures the bending of light as it passes through the stone. Genuine tanzanite typically has a specific gravity of around 3.35 and a refractive index of approximately 1.70. These values can be measured using specialized equipment by a qualified gemologist or jeweler.
6. Gemological Certification: A Mark of Authenticity
Obtaining a gemological certification from a reputable laboratory is one of the most reliable ways to ensure the authenticity of a tanzanite. Gemological laboratories, such as the Gemological Institute of America (GIA) or the American Gem Society (AGS), conduct rigorous testing and analysis to verify the identity and quality of gemstones. A gemological certificate typically includes details such as the gemstone’s weight, measurements, color, clarity, and any treatments that have been performed.
7. Ethical Sourcing: Ensuring Responsible Practices
When purchasing tanzanite, it’s essential to consider the ethical and responsible sourcing of the gemstone. Tanzanite is mined primarily in Tanzania, and it’s important to ensure that the mining practices adhere to environmental and social standards. Look for tanzanite that is certified by organizations such as the Responsible Jewellery Council (RJC), which promotes responsible practices throughout the jewelry supply chain.
Key Points: A Journey of Authenticity
Identifying genuine tanzanite requires a combination of knowledge, observation, and professional expertise. By carefully examining the color, clarity, pleochroism, fluorescence, specific gravity, refractive index, and gemological certification, you can increase your chances of acquiring an authentic tanzanite. Additionally, supporting ethical sourcing practices ensures that your purchase contributes to responsible and sustainable mining operations. With careful consideration and informed choices, you can confidently invest in the captivating beauty and genuine nature of tanzanite.
Basics You Wanted To Know
- Q: Is it possible to find tanzanite in colors other than blue-violet?
- A: Natural tanzanite typically exhibits a blue-violet hue, but heat treatment can produce a range of colors, including green, yellow, and orange. However, these treated tanzanites may not possess the same value as untreated stones.
- Q: How can I tell if a tanzanite has been heat-treated?
- A: Heat treatment is a common practice to enhance the color and clarity of tanzanite. While heat-treated tanzanites are generally considered genuine, they may have a lower value than untreated stones. To determine if a tanzanite has been heat-treated, consult a qualified gemologist or jeweler for professional evaluation.
- Q: What is the difference between natural and synthetic tanzanite?
- A: Natural tanzanite is mined from the earth, while synthetic tanzanite is created in a laboratory. Synthetic tanzanites are chemically and optically similar to natural tanzanites, but they lack the natural inclusions and characteristics that are found in genuine gemstones. Synthetic tanzanites are generally less valuable than natural tanzanites.
