Pretty Blue Sapphire Crystal 10.21 carats - MADAGASCAR - Height: 11 mm - Width: 8 mm- 2.04 g - (1)

Discover this remarkable 10.21-carat natural rough sapphire from Madagascar, one of the world’s most prestigious regions for the diversity and beauty of its gemstones.

This superb crystal stands out for its intense blue color, combining magnificent shades of royal blue, azure blue, and deep blue. Under transmitted light, its color reveals an especially captivating brightness, highlighting the full complexity of its internal structure.

Its compact, geometric morphology, together with its well-defined crystal faces, gives it a remarkable presence.

One of the most interesting features of this stone is its many growth structures and natural inclusions, which form a veritable network of patterns inside the crystal.

Light passes through certain areas of the sapphire, revealing luminous blue shades, while the denser sections display a deep, rich color.

At 10.21 carats and measuring 11 × 8 × 8 mm, this specimen has substantial volume and a pleasing thickness.

An especially interesting piece for collectors of natural gemstones, mineralogy enthusiasts, and admirers of corundum crystals.


Technical specifications


- Gemstone: Natural rough sapphire
- Mineral family: Corundum
- Origin: Madagascar
- Weight: 10.21 carats (2.042 grams)
- Dimensions: 11 × 8 × 8 mm
- Color: Intense blue, with royal blue and azure blue shades
- Transparency: Translucent under transmitted light, with visible inclusions
- Morphology: Compact rough crystal with a geometric structure
- Luster: Vitreous on some surfaces
- Chemical composition: Al₂O₃
- Hardness: 9 on the Mohs scale
- Condition: Rough, with natural growth structures and inclusions
- Intended use: Mineral collection, gemology, lapidary study


Madagascar – An exceptional land in the history of gemstones


Madagascar is now considered one of the world’s major gemological regions.

Located in the Indian Ocean, this vast island has an extraordinary geological history stretching back several hundred million years.

Once part of the supercontinent Gondwana, Madagascar experienced major tectonic and metamorphic events that contributed to the formation of an exceptional diversity of minerals.

Its subsoil contains sapphires, rubies, tourmalines, garnets, aquamarines, and many other sought-after gems.

The modern history of Malagasy sapphires took a major turn during the 1990s.

The discovery of several significant deposits gradually attracted the attention of international traders and industry professionals.

In 1998, the discovery of the vast deposits at Ilakaka, in the country’s southwest, marked a major event in the global history of sapphire.

This region quickly became one of the world’s most important sapphire mining and trading centers.

Other locations, notably Andranondambo, Andilamena, and Sakaraha, have also contributed to the international reputation of Malagasy corundum.

Madagascar sapphires are especially prized for their extraordinary range of colors.

Blue, pink, purple, yellow, and orange stones are found there, as well as varieties displaying several shades within a single crystal.

Some top-quality blue sapphires can rival stones from historic regions such as Sri Lanka or Kashmir.

Madagascar now holds an essential place in the international trade of natural sapphires.


Magnificent royal blue color with deep shades


The most captivating feature of this specimen is undoubtedly its superb blue color, which is particularly luminous under transmitted light.

The crystal has an intense blue dominant color, accompanied by lighter shades and deep blue areas.

This natural variation in color creates remarkable visual depth.

The light also reveals a particularly interesting internal architecture, made up of numerous growth lines and inclusions.

The blue hues of sapphires are primarily due to traces of iron and titanium in their crystal structure.

These elements interact with light to produce the magnificent shades characteristic of blue sapphires.

For centuries, sapphires with intense blue colors have been particularly sought after in jewelry and among collectors.

Shades reminiscent of royal blue are among the most prized, especially when they display beautiful saturation and remarkable chromatic depth.

This crystal has a color reminiscent of these prestigious hues, although the official gemological classification “Royal Blue” cannot be determined from a photograph.

A magnificent rough stone whose color is a true aesthetic attraction.


A 10.21-carat crystal with remarkable morphology


At 10.21 carats, this sapphire has a striking presence for a rough specimen.

Its dimensions of 11 × 8 × 8 mm give it a compact, substantial, and particularly interesting shape.

Its geometric morphology reveals several crystal surfaces, with outlines characteristic of a natural crystal.

Under transmitted light, the stone reveals a complex internal structure.

The many visible growth lines and inclusions create a fascinating network of intersecting patterns.

Some areas of the crystal allow more light to pass through, revealing a luminous azure blue, while others display a deeper color.


This combination of shades and internal structures gives the stone a unique character.


This specimen stands out in particular for:

- Its substantial weight of 10.21 carats.
- Its magnificent intense blue color.
- Its royal blue and azure blue shades.
- Its compact, geometric morphology.
- Its pleasing thickness of 8 mm.
- Its translucency under transmitted light.
- Its many visible growth structures.
- Its origin in Madagascar, world-renowned for its sapphires.
These characteristics make it an especially appealing piece for admirers of natural corundum.


A fascinating geological formation


Sapphire belongs to the corundum family, minerals composed primarily of aluminum oxide, with the chemical formula Al₂O₃.

With a hardness of 9 on the Mohs scale, it is among the natural minerals most resistant to scratching.

Only diamond, among the reference minerals on this scale, has a higher hardness.

Natural sapphires can form in various geological environments, including certain metamorphic rocks and settings associated with magmatic processes.

In Madagascar, ancient geological transformations created favorable conditions for the crystallization of many corundums.

During their formation, these crystals can incorporate chemical elements responsible for their color, as well as various natural inclusions.

Variations in growth conditions can also leave characteristic internal structures.

On this specimen, these features are especially visible under transmitted light.

The many lines and inclusions reveal a complex internal architecture, providing a true record of its geological history.

Each crystal therefore has its own distinctive structure.


Rough sapphires – Sought-after pieces for collectors


While cut sapphires are highly valued in jewelry for their brilliance and color, rough crystals have a different mineralogical appeal.

They make it possible to observe the natural characteristics of corundum directly, including its morphology, crystal surfaces, and internal structures.

Collectors particularly appreciate specimens with beautiful color, interesting morphology, and a recognized origin.

This Madagascar sapphire brings together several of these qualities.

Its intense blue immediately catches the eye, while its inclusions and growth lines offer many details to discover.

Its compact shape and weight of over 10 carats also enhance its appeal as a collector’s piece.

It would make a fitting addition to a collection devoted to rough gemstones, corundum, or minerals from Madagascar.

It is also an interesting specimen for gemological observation.

Any potential lapidary work would, however, require a preliminary examination of the visible inclusions and fractures to assess the cutting possibilities.
A sapphire steeped in history and symbolism
Since antiquity, sapphires have held a special place among gemstones.

Their blue color has long been associated with royalty, wisdom, and nobility.

Over the centuries, these gems have adorned many prestigious pieces of jewelry and historic objects.

To this day, blue sapphires remain among the most iconic and highly prized gemstones.

Rough crystals offer a glimpse of another facet of their beauty: the stone as it formed in nature.

This Madagascar specimen perfectly illustrates this appeal, with its intense color, fascinating internal structures, and natural morphology.


Conclusion – A superb 10.21-carat blue sapphire from Madagascar


This exceptional natural rough sapphire from Madagascar, weighing 10.21 carats and measuring 11 × 8 × 8 mm, stands out for its magnificent intense blue color, royal blue shades, and particularly interesting crystal architecture.

Its translucency under transmitted light makes it possible to appreciate the many inclusions and growth structures that characterize this natural stone.

Its compact morphology, substantial weight, and prestigious origin make it a magnificent piece for gemstone collectors and mineralogy enthusiasts.

A remarkable 10.21-carat rough sapphire, combining the depth of blue, the beauty of natural crystals, and Madagascar’s exceptional gemological heritage.




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