The Marcial de Gomar Star Emerald
The Largest Known Double-Sided Star Emerald Ever Recorded
Among the world’s rarest gemstones, few specimens can claim true singularity. The Marcial de Gomar Star Emerald stands alone as one of the most extraordinary emerald discoveries of the modern era, recognized as the largest known double-sided star emerald ever documented and among the rarest examples of asterism in any emerald species.
Weighing 25.86 carats, this exceptional gemstone represents a phenomenon so uncommon that, until recent decades, the existence of star emeralds remained virtually unknown to gemological science. The Marcial de Gomar Star Emerald occupies a unique place in gemstone history, combining exceptional size, remarkable optical properties, and documented provenance, making it a specimen worthy of the world’s finest museums, royal treasuries, and elite private collections.
A Gemological Rarity Without Equal
Asterism, the star-like optical phenomenon prized in rubies and sapphires, is exceptionally rare in emerald. For much of the twentieth century, no documented examples of asterism in emerald beryl were known to the gemological community.
In his landmark 1981 work Emeralds and Other Beryls, noted gemologist John Sinkankas highlighted that extensive investigations, including research conducted by the Gemological Institute of America (GIA), had failed to identify confirmed examples of star emeralds. Against this historical backdrop, the Marcial de Gomar Star Emerald emerged as a discovery of extraordinary significance.
Today, the gemstone is recognized among the very few recorded star emeralds known to science and is distinguished as the only documented double-sided star emerald, a characteristic that elevates it into a category entirely of its own.
Discovery of an Extraordinary Specimen
The story of the Marcial de Gomar Star Emerald began in 1997 when an unusual rough emerald crystal was acquired from an emerald dealer in Madagascar. Initially set aside among a collection of rough gemstones, the specimen attracted renewed attention several years later when renowned emerald expert Manuel Marcial de Gomar detected unusual optical characteristics within the crystal.
Suspecting the presence of chatoyancy, commonly known as the cat’s-eye effect, Marcial commissioned a master emerald cutter to fashion the stone as a double cabochon, a highly unconventional choice for emeralds. This decision would ultimately reveal one of the most remarkable gemological phenomena ever observed in the species.
Upon completion, the gemstone exhibited a unique play of light that defied conventional explanation. Rather than producing the single moving band associated with cat’s-eye gems, the emerald reflected light in multiple directions, revealing a complex optical display unlike anything previously encountered.
Recognizing the specimen’s unusual nature, Marcial preserved the gemstone for further study, understanding that its true significance had yet to be fully understood.
From Hidden Treasure to Gemological History
For nearly a decade, the emerald remained safely stored while additional research and examination were contemplated. Its importance became increasingly apparent during the assembly of a landmark collection representing more than seventy years of involvement by the Marcial family in the international emerald and gemstone trade.
The turning point came when the stone was examined by renowned gemologist and appraiser Martin Fuller of Martin Fuller & Associates. Having studied some of the world’s most celebrated gems, including the legendary Hope Diamond housed at the Smithsonian Institution, Fuller immediately recognized the potential significance of the specimen.
Under specialized observation and lighting conditions, the gemstone revealed the unmistakable presence of asterism, the rare star effect that had eluded recognition for years.
Fuller recommended submission to the Gemological Institute of America for advanced analysis and confirmation.
Certified and Recognized by the Gemological Institute of America
On July 16, 2013, the Marcial de Gomar Star Emerald was formally identified and certified, securing its place within gemological history.
The gemstone has since been referenced multiple times within the prestigious Gems & Gemology journal published by the Gemological Institute of America, in their Fall 2015 magazine and referenced again in Summer 2025 edition. Experts have identified it as the largest recorded star emerald specimen known at the time of publication and among only a handful of authenticated examples documented worldwide.
Its significance extends beyond rarity alone. The combination of exceptional size, documented asterism, double-sided star formation, and well-established provenance places the Marcial de Gomar Star Emerald among the most important collector-grade emeralds ever discovered.
Recognized and featured in Gem-A Gems & Jewellery August 2017
The Marcial de Gomar Star Emerald was featured in the Autumn 2017 issue of Gems & Jewellery magazine, published by Gem-A. The article, authored by Carl A. Schütze, examined the gem’s history, certification, and significance as a star emerald specimen.
A Legacy Gem for Museums, Royal Collections, and Future Generations
More than a gemstone, the Marcial de Gomar Star Emerald represents a landmark achievement in gemology and a lasting contribution to the history of natural treasures.
Its eighteen-year journey from rough crystal to internationally recognized rarity reflects the dedication, expertise, and vision of the late Manuel Marcial de Gomar, whose lifelong pursuit of exceptional gemstones brought this extraordinary specimen to light.
Today, the Marcial de Gomar Star Emerald stands as an enduring symbol of rarity, discovery, and natural wonder, a museum-quality treasure destined to remain among the most important emerald specimens ever recorded.