Corundum with Muscovite

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Purplish red crystals of corundum, this is the variety known as Ruby, on a calcite matrix with muscovite. In good condition. Chumar and the surrounding Ruby Valley, situated within the Dhading District of Bagmati Pradesh, Nepal, occupy a remote, high-altitude sector of the Ganesh Himal range in the central Himalayas. Geologically, the region's ruby occurrences formed as a result of intense regional metamorphism during the collision of the Indian and Asian tectonic plates. Ancient limestone and sedimentary sequences were transformed into marble lenses under extreme heat and pressure, allowing chromium-bearing fluids to interact with the host rock and crystallize gem-quality corundum. Historically, local gemstone and mineral deposits in the valley gained widespread attention following exploratory geological surveys and local discoveries primarily in the late 20th century, though commercial extraction has remained limited and sporadic due to the extreme terrain, harsh weather, and isolated high-altitude conditions.