Introduction

Natural 6.31 Carats Oval Tanzanite is one of the most captivating gemstones in today’s fine jewelry market. Known for its deep violet-blue hue and exceptional brilliance, this rare stone has become a symbol of luxury and exclusivity. Many collectors, jewelers, and enthusiasts consider tanzanite a once-in-a-generation gemstone due to its unique geographic origin and striking color-changing properties. This article explores everything you need to know about the Natural 6.31 Carats Oval Tanzanite, from its origin to its value, buying tips, and care instructions.

Tanzanite has only been discovered in one place on Earth: the Merelani Hills of Tanzania. This makes every Natural 6.31 Carats Oval Tanzanite a geological treasure formed under rare and specific conditions. Its exceptional saturation, combined with a well-cut oval shape, gives this gem extraordinary light performance and unparalleled beauty. Buyers looking for a standout piece often gravitate toward stones above 6 carats, as they display the color depth and clarity that set high-end tanzanites apart.

Whether you are a gemstone investor, a jewelry designer, or someone searching for a meaningful and luxurious gift, understanding the characteristics of a Natural 6.31 Carats Oval Tanzanite is essential. This guide provides everything from scientific details and grading factors to care tips, market value, and frequently asked questions, all written in a clear and accessible format.

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Main Content

What Is Natural 6.31 Carats Oval Tanzanite?

Natural tanzanite is a blue to violet gemstone from the zoisite mineral family. A Natural 6.31 Carats Oval Tanzanite is a premium-sized stone with a mass of 6.31 carats and an oval cut optimized for brilliance and color performance. This size places it in the investment-grade category, due to the rarity of high-clarity stones above 5 carats.

Geological Origin

Tanzanite was discovered in the 1960s and quickly gained recognition for its exotic color combination and limited source. It is found only in Tanzania, near Mount Kilimanjaro. Scientists estimate that the deposits may be depleted within a few decades, making large natural stones like the 6.31 carat variety increasingly valuable.

Color Characteristics

The signature feature of Natural 6.31 Carats Oval Tanzanite is its pleochroism. Pleochroism refers to a gemstone’s ability to show multiple colors depending on light direction. Tanzanite can display:

• Deep blue

• Violet blue

• Purplish blue

The oval cut enhances these shifting tones by allowing more surface area for light reflection.

Why the Oval Cut Matters

An oval cut is one of the most efficient shapes for tanzanite because:

• It maximizes brilliance

• It preserves carat weight

• It reduces material loss during cutting

• It enhances the gemstone’s face-up appearance

For a 6.31 carat stone, this shape ensures a balanced combination of elegance and visual impact.

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Physical and Optical Properties

Hardness and Durability

Tanzanite scores 6 to 7 on the Mohs scale, making it suitable for jewelry but requiring careful handling. Its cleavage direction means it can break if struck at certain angles, so proper setting design is crucial.

Optical Features

• Refractive index: 1.688 – 1.700

• Birefringence: 0.006 – 0.018

• Crystal system: Orthorhombic

These optical characteristics give Natural 6.31 Carats Oval Tanzanite its strong fire and vivid saturation.

Heat Treatment

Most tanzanites, including larger stones, undergo heat treatment to achieve desirable blue hues. This process is stable and permanent. Heat treatment does not reduce the value of the gemstone as long as the stone remains natural and untreated by artificial diffusion or coatings.

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Value and Pricing of Natural 6.31 Carats Oval Tanzanite

The value of a Natural 6.31 Carats Oval Tanzanite depends on several grading factors. Prices for top-quality stones of this size usually range from 700 to 1500 USD per carat, and exceptional specimens may exceed this range.

Key Factors Influencing Price

 1. Color Quality

The most valuable tanzanites display a deep, rich violet blue with even saturation. Stones that lean too pale or overly violet are considered lower tier.

2. Clarity

A premium-quality Natural 6.31 Carats Oval Tanzanite should have:

• Eye-clean clarity

• Minimal visible inclusions

• A transparent, bright appearance

Inclusions reduce brilliance and value, especially in large stones.

3. Cut Precision

An ideal oval cut maximizes scintillation and ensures symmetry across all facets. Poorly proportioned stones may appear dull or windowed.

4. Carat Weight

A 6.31 carat tanzanite is considered large, making it more desirable for collectors. Rarity increases exponentially with size.

5. Certification

A certificate from a reputable lab such as:

• GIA (Gemological Institute of America)

• IGI (International Gemological Institute)

• GRS (GemResearch SwissLab)

helps verify authenticity and improves resale value.

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How to Buy a Natural 6.31 Carats Oval Tanzanite

Buying a gemstone of this size requires careful evaluation. The following guidelines ensure you make a safe and informed purchase.

Buy from Trusted Sellers

Choose reputable gemstone dealers, certified jewelers, or verified online platforms. Look for customer reviews, return policies, and gem reports.

Inspect Color and Clarity

If purchasing online, request:

• High-resolution photos

• 360-degree videos

• Microscopic inclusion images

For in-person purchases, assess the color under daylight-equivalent lighting.

Ask for a Certificate

Never buy a high-carat tanzanite without proper gemological paperwork. Certification protects your investment and confirms the stone’s natural origin.

Compare Prices

Use multiple sources to compare price ranges. High-quality tanzanite above 6 carats is rare, so price may vary significantly between sellers.

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Best Settings for Natural 6.31 Carats Oval Tanzanite

A stone of this size deserves a setting that highlights its brilliance and protects its structure.

Popular Setting Styles

• Halo setting: Maximizes brilliance and emphasizes shape

• Solitaire setting: Classic and minimalistic

• Three-stone setting: Symbolic and elegant

• Bezel setting: Excellent for protection

Metal Choices

• White gold: Enhances blue tones

• Platinum: Durable and premium

• Yellow gold: Creates a warm contrast with the cool gemstone

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How to Care for Natural 6.31 Carats Oval Tanzanite

Tanzanite requires gentle handling due to its sensitivity to impact.

Cleaning Instructions

• Use warm soapy water

• Avoid ultrasonic cleaners

• Use a soft brush to remove dust and oils

Storage Tips

• Store separately from other gems

• Use a padded jewelry box

• Avoid extreme temperature changes

Wearing Precautions

Avoid wearing tanzanite jewelry during:

• Sports

• Heavy manual work

• Activities with risk of impact

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Conclusion

Natural 6.31 Carats Oval Tanzanite is a rare and breathtaking gemstone that combines geological uniqueness with exceptional visual beauty. Its deep violet blue color, large size, and oval cut make it an excellent choice for collectors and jewelry lovers alike. As tanzanite sources continue to decline, stones above 6 carats are becoming increasingly valuable in the global market. Understanding its properties, pricing factors, and care requirements helps ensure you make a wise and rewarding investment.

Whether you plan to purchase this gem for personal wear or as part of a gemstone collection, the Natural 6.31 Carats Oval Tanzanite stands as a symbol of luxury, rarity, and timeless elegance.

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FAQ (Frequently Asked Questions)

1. Is Natural 6.31 Carats Oval Tanzanite rare?

Yes. Tanzanite is mined in only one region in the world, and stones above 6 carats with high clarity are extremely rare and valuable.

2. Does tanzanite change color?

Yes. Tanzanite exhibits pleochroism, meaning it shows different shades of blue and violet depending on lighting and viewing angle.

3. Is heat treatment normal for tanzanite?

Yes. Almost all natural tanzanites are heat treated to enhance their natural blue color. The treatment is stable and accepted in the industry.

4. How much is a 6.31 carat tanzanite worth?

Depending on color, clarity, and cut, it can range from 700 to 1500 USD per carat, with premium stones priced higher.

5. Is tanzanite durable for daily wear?

Tanzanite is softer than diamonds or sapphires, so daily wear requires caution. Proper setting and regular care help protect the stone.

6. What is the best shape for tanzanite?

The oval cut is highly recommended due to its ability to enhance brilliance and retain carat weight.

7. Is tanzanite good for investment?

Yes. Because of limited supply and increasing demand, larger natural tanzanites are considered excellent long-term investments.