The remote Himalayan region of Kashmir produced what many experts consider the world's finest sapphires during a brief period in the late 19th century. Discovered around 1881 following a landslide high in the Zanskar Range, these sapphires exhibit an incomparable velvety blue color often described as "blue velvet" or "cornflower blue." Mining conditions at elevations above 15,000 feet proved extremely challenging, with harsh weather limiting operations to just a few summer months. By the early 1900s, the original deposit was largely exhausted, making authentic Kashmir sapphires incredibly rare and valuable. Modern attempts to reopen these mines have yielded minimal results, further cementing the legendary status of these gems, which command astronomical prices at international auctions.
Colombia produces approximately 70-90% of the world's finest emeralds, with most coming from three main mining areas in the departments of Boyacá and Cundinamarca, collectively known as the "Emerald Triangle." The Muzo mine, perhaps the most famous, yields emeralds with a distinctive warm, slightly bluish-green color. Chivor, an ancient mine once worked by indigenous peoples and later by Spanish colonizers, produces emeralds with a cooler, more bluish cast. The newest significant mining area, Coscuez, rounds out the triangle. Colombian emeralds are prized for their exceptional color saturation and fire, formed through a unique hydrothermal process different from emeralds found elsewhere. Their geological formation in sedimentary host rock, rather than the more common metamorphic or igneous settings, contributes to their distinctive characteristics.
While Burmese (Myanmar) rubies historically set the standard for excellence, significant discoveries in Mozambique have transformed the ruby market since 2009. The Montepuez ruby deposit in northeastern Mozambique has emerged as the world's most productive source of fine rubies, yielding stones that rival Myanmar's finest. These rubies display excellent transparency and a vibrant red color, sometimes with slight purplish undertones. Mozambique's favorable mining conditions allow for more consistent production than Myanmar's increasingly depleted and politically complicated Mogok Stone Tract. Responsible mining initiatives by companies like Gemfields have established sustainable practices at Montepuez, emphasizing environmental management, worker safety, and community development—a stark contrast to the artisanal, often problematic mining methods in many traditional gem-producing regions.
Tanzania has emerged as one of the world's most diverse gemstone sources, producing an extraordinary variety of high-quality crystals. The discovery of tanzanite in 1967—a blue-violet variety of zoisite found nowhere else on Earth—put the country on the gemological map. The Mahenge region yields exceptional spinel crystals in vivid pinks and reds that rival fine rubies in appearance. Merelani produces tsavorite garnet—a vibrant green gem discovered by British geologist Campbell Bridges—while the Umba Valley yields virtually every color of sapphire, including rare color-change varieties. Additionally, Tanzania is known for rhodolite garnet, color-change alexandrite, and chrome tourmaline. The country's remarkable geological diversity, created through complex tectonic processes where different terranes collided, explains this extraordinary concentration of gem wealth.
The global map of gemstone production continues to evolve as new discoveries emerge and traditional sources decline. Madagascar has become a major player, producing fine sapphires, rubies, and emeralds that challenge historical sources. Namibia yields exceptional tourmaline, while Afghanistan continues to produce superb emeralds, sapphires, and lapis lazuli despite political instability. Technological advances in mining, from ground-penetrating radar to advanced recovery systems, have revolutionized how deposits are identified and worked. Simultaneously, growing concerns about environmental impact and ethical sourcing have transformed industry practices. Organizations like the Responsible Jewellery Council and initiatives such as the Kimberley Process for diamonds reflect a shifting emphasis toward sustainability and transparency in a trade historically marked by opacity and exploitation.