4.45 ct MYSORE STAR RUBY – INDIA

The Mysore Star Ruby is a gemstone that carries the deep, regal soul of Southern India. A variety of Corundum, it is legendary for its intense "Indian Red"—a saturated, purplish-red hue that is distinct from the "pigeon’s blood" of Burma. I have always been captivated by its sharp, six-rayed star, known as asterism, which glides across the surface of the cabochon like a celestial compass. Unlike many modern rubies that are "glass-filled" or diffusion-treated, the true Mysore stones are prized for their natural, rugged character. To hold a Mysore Star Ruby is to hold a piece of history from the ancient mines of Karnataka; it is a stone of dignity and fire, offering a mysterious internal depth that seems to glow even in low light.

Historical Significance: Mysore Rubies have been a part of the royal treasury of the Maharajas for centuries. Historically, the Mysore region was the primary source of the world’s star rubies before the discovery of African deposits. These stones were revered as "the king of gems" in Vedic astrology and were often set in the center of ceremonial jewelry to represent the sun. In the world of fine gems, the Mysore Star is celebrated for its well-defined asterism, which is caused by the perfect alignment of rutile needles. It stands as a symbol of the enduring legacy of Indian mineralogy, bridging the gap between ancient royal tradition and the peak of modern "connoisseur" collecting.

Discovery: The ruby deposits in the Channapatna and Maddur areas of the Mysore district have been known for generations. Scientifically, these rubies formed in high-grade metamorphic rocks (schists and gneisses). Their discovery was vital for the early gem trade in India, establishing the country as a world leader in the production of phenomenal (star) gemstones long before modern mining techniques were developed.

Important Mines: The most legendary source is the Mysore District in Karnataka, India. While many of the original mines are now strictly regulated or depleted, "old stock" Mysore material remains the gold standard for Indian Star Rubies. I also have a high regard for the star rubies from Kangayam in Tamil Nadu. For the vault, I prioritize these older Mysore pieces for their superior star definition and their characteristic "silky" texture, which gives the red color a depth that modern synthetics simply cannot replicate.

Description: Mysore Star Ruby is a variety of Corundum (aluminum oxide) colored by chromium, crystallizing in the trigonal system. It sits at a 9 on the Mohs scale, making it the second hardest natural mineral and exceptionally durable for any type of jewelry. It is characterized by its vitreous to sub-adamantine luster and its deep, opaque-to-translucent purplish-red color.[Image showing the "Silk" (rutile needles) inside a Mysore Ruby that creates the 6-rayed star through light reflection]

One of its most identifying traits is its asterism. This optical phenomenon is caused by light reflecting off microscopic, needle-like inclusions of Rutile (known as "silk") that intersect at 60-degree angles. It has a high refractive index ($n \approx 1.76$ to $1.77$). Because Mysore rubies are often more included than their Burmese cousins, they produce some of the sharpest and most stable stars in the world. When I cut a Mysore Star Ruby, I carefully orient the "c-axis" to be perfectly perpendicular to the top of the cabochon, ensuring the star is centered and vibrant. It is a dense, high-vibration mineral that represents the absolute pinnacle of Indian phenomenal gems.

Chemical Formula: Al₂O₃:Cr