Chlorastrolite, often dubbed the "Uleuxite of Lake Superior," is a captivating gemstone found only in a very limited area of the Lake Superior region. Its striking green coloration, often interspersed with intricate patterns, has captivated collectors and mineral enthusiasts for decades. While the Smithsonian doesn't specifically have a publicly accessible online database cataloging every single specimen in its vast collection, its renowned mineralogical holdings undoubtedly include examples of this rare and beautiful stone. This article delves into the characteristics, history, and significance of gem-quality chlorastrolite, focusing on its appeal and why it's a sought-after collectible.
What is Chlorastrolite?
Chlorastrolite is a relatively rare, fibrous silicate mineral belonging to the pumpellyite group. Its chemical formula is (Ca,Na)₂(Al,Fe)₃(Si,Al)₂O₁₀(OH)₂·H₂O. The vibrant green color, ranging from a light seafoam to a deep emerald, is due to the presence of iron and other trace elements. Its characteristic feature is its intricate, radiating patterns resembling starbursts or swirling galaxies, creating unique and visually stunning pieces. The intense, almost electric, green hue is what sets high-quality specimens apart.
Where is Chlorastrolite Found?
Exclusively found along the northern shores of Lake Superior, primarily in the Apostle Islands of Wisconsin, chlorastrolite's limited geographical distribution greatly contributes to its rarity. The precise locations are often kept secret by collectors and local enthusiasts to protect these fragile natural formations. This restricted locale adds to its allure and collector value.
What Makes Chlorastrolite Gem-Quality?
Several factors contribute to the classification of chlorastrolite as gem-quality:
- Intense Color: A deep, vibrant green is crucial. Pale or dull specimens are less desirable.
- Translucency: Gem-quality chlorastrolite exhibits translucency, allowing light to pass through, showcasing its internal patterns.
- Clarity: Fewer inclusions and minimal fractures are key.
- Pattern: Intricate and striking radiating patterns are highly prized, making each piece unique.
- Size and Cut: Larger, well-cut specimens command higher value.
Is Chlorastrolite Valuable?
The value of chlorastrolite varies considerably based on the factors mentioned above. High-quality, intensely colored, large, and well-patterned specimens are considered extremely valuable among collectors. While it's not as widely known or traded as diamonds or emeralds, its rarity and unique beauty warrant a significant price for exceptional pieces.
How Can I Identify Genuine Chlorastrolite?
Due to its limited geographical source and unique appearance, authentic chlorastrolite is relatively easy to identify. However, be wary of imitations or mislabeled stones. The key features are the vibrant green color, translucency, radiating patterns, and origin from the Lake Superior region.
Does the Smithsonian Museum Have Chlorastrolite?
While a detailed online inventory isn't readily available for every item in the Smithsonian's extensive collection, given their commitment to comprehensive mineralogical holdings, it's highly probable that their collection contains specimens of chlorastrolite. The museum's curatorial staff would be the best source of confirmation for the presence of specific chlorastrolite samples.
What is the Difference Between Chlorastrolite and other Green Stones?
Chlorastrolite's unique combination of vibrant green color, translucency, and intricate radiating patterns distinguishes it from other green gemstones like jade, aventurine, or green tourmaline. Its distinctive starburst patterns are its most recognizable and defining characteristic.
Conclusion:
Chlorastrolite is a truly remarkable gem, a testament to the Earth's ability to produce stunning natural wonders. Its limited availability, striking beauty, and intriguing history have secured its place as a sought-after collectible among mineral enthusiasts and gemstone collectors worldwide. Although specific Smithsonian holdings may not be publicly detailed online, the museum's renowned collection undoubtedly includes examples of this exceptional Lake Superior treasure.
